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PUBLICATIONS AND CREATIVE ACTIVITIES


(A) Scientific Software:

We have authored/co-authored 12 nanoelectronics software that have been published (with DOI) on National Science Foundation’s nanoHUB.org and freely available for public use. As of June 6, 2019, these simulators have served over 19,800 individual users worldwide running over 860,000 simulations. (https://nanohub.org/members/9293/usage). Listed below are the references:

  1. Shaikh S. Ahmed; Dragica Vasileska (2014), “QuaMC2D,” https://nanohub.org/resources/quamc2d. (DOI: 10.4231/D3542J801).

  2. Dragica Vasileska; Shaikh S. Ahmed; Gokula Kannan; Matteo Mannino; Gerhard Klimeck; Mark Lundstrom; Akira Matsudaira; Junzhe Geng (2013), “Schred,” https://nanohub.org/resources/schred. (DOI: 10.4231/D3HT2GB8Z).

  3. Neophytos Neophytou; Shaikh S. Ahmed; Eric Polizzi; Gerhard Klimeck; Mark Lundstrom (2012), “CNTFET Lab,” https://nanohub.org/resources/cntfet. (DOI: 10.4231/D32B8VB3H).

  4. M. P. Anantram; Shaikh S. Ahmed; Alexei Svizhenko; Derrick Kearney; Gerhard Klimeck (2011), “NanoFET,” https://nanohub.org/resources/nanofet. (DOI: 10.4231/D34T6F314).

  5. Zhibin Ren; Sebastien Goasguen; Akira Matsudaira; Shaikh S. Ahmed; Kurtis Cantley; Yang Liu; Mark Lundstrom; Xufeng Wang (2013), “NanoMOS,” https://nanohub.org/resources/nanomos. (DOI: 10.4231/D3J96090H).

  6. Gerhard Klimeck; Akira Matsudaira; Shaikh S. Ahmed; Dragica Vasileska; Saumitra Raj Mehrotra; Xufeng Wang (2014), “MOSCap,” https://nanohub.org/resources/moscap. (DOI: 10.4231/D3TM72116).

  7. Shaikh S. Ahmed; Saumitra Raj Mehrotra; SungGeun Kim; Matteo Mannino; Gerhard Klimeck; Dragica Vasileska; Xufeng Wang; Himadri Pal; Gloria Wahyu Budiman (2014), “MOSFet,” https://nanohub.org/resources/mosfet. (DOI: 10.4231/D3WW7704N).

  8. Anisur Rahman; Jing Guo; Md. Sayed Hasan; Yang Liu; Akira Matsudaira; Shaikh S. Ahmed; Supriyo Datta; Mark Lundstrom (2014), “FETToy,” https://nanohub.org/resources/fettoy. (DOI: 10.4231/D3RV0D12Z).

  9. Richard Akis; Shaikh S. Ahmed; Mohammad Zunaidur Rashid; David K. Ferry (2015), "Quantum Point Contact,” https://nanohub.org/resources/qpc. (DOI: 10.4231/D3H70817B).

  10. Allison Anne Campbell; Mohammad Zunaidur Rashid; Afsana Sharmin; Shaikh S. Ahmed (2015), “Multiscale Modeling of Thermoelectric Cooler,” https://nanohub.org/resources/multiscaletec. (DOI: 10.4231/D3707WP8J).

  11. Shaikh S. Ahmed; Vinay Uday Chimalgi; Katina Mattingly; Krishna Kumari Yalavarthi (2015), “Nanoscale Solid-State Lighting Device Simulator,” https://nanohub.org/resources/nanossl. (DOI: 10.4231/D3DR2P94F).

  12. Mohammad Zunaidur Rashid; Sasi Sekaran Sundaresan; Shaikh S. Ahmed (2017), “Monte Carlo Phonon Transport Simulator,” https://nanohub.org/resources/mcpt. (DOI: 10.4231/D3HX15S96)

 

(B) Book Chapters:

  1. Shaikh Ahmed, Neerav Kharche, Rajib Rahman, Muhammad Usman, Sunhee Lee, Hoon Ryu, Hansang Bae, Steve Clark, Benjamin Haley, Maxim Naumov, Faisal Saied, Marek Korkusinski, Rick Kennel, Michael Mclennan, Timothy B. Boykin, and Gerhard Klimeck, “Multimillion Atom Simulation of Electronic and Optical Properties of Nanoscale Devices using NEMO 3-D,” Encyclopedia of Complexity and Systems Science, pp. 1–69, Springer Berlin Heidelberg, Ed. Robert A. Meyers, Latest Version 24 July 2015.

  2. Abdussamad Muntahi and Shaikh Ahmed, “MOSCap Tool on nanoHUB.org,” World Scientific Review Volume, accepted and with editor, 2016.

  3. Abdussamad Muntahi, Dragica Vasileska, and Shaikh Ahmed, “A Primer on the MOSFET Simulator on nanoHUB.org,” World Scientific Review Volume, accepted and with editor, 2016.

  4. Shaikh Ahmed, Mihail Nedjalkov, and Dragica Vasileska, “Comparative Study of Various Self-Consistent Event Biasing Schemes for Monte Carlo Simulations of Nanoscale MOSFETs,” Theory and Applications of Monte Carlo Simulations, Ed. Wai Kin (Victor) Chan, Chp. 5, pp. 109–133, 2013.

  5. Shaikh Ahmed, Krishna Kumari Yalavarthi, Vamsi Gaddipati, Abdussamad Muntahi, Sasi Sundaresan, Shareef Mohammed, Sharnali Islam, Ramya Hindupur, Dylan John, and Joshua Ogden, “Quantum Atomistic Simulations of Nanoelectronic Devices using QuADS,” Nano-Electronic Devices: Semiclassical and Quantum Transport Modeling, Eds. D. Vasileska and S. M. Goodnick, Springer, pp. 405–441, 2011.

  6. D. Vasileska, H. R. Khan, S. S. Ahmed, G. Kannan and C. Ringhofer, “Quantum and Coulomb Effects in Nanodevices,” Nano-Electronic Devices: Semiclassical and Quantum Transport Modeling, Ed. D. Vasileska and S. M. Goodnick, pp. 97–182, Springer, 2011.

  7. Shaikh Ahmed, Neerav Kharche, Rajib Rahman, Muhammad Usman, Sunhee Lee, Hoon Ryu, Hansang Bae, Steve Clark, Benjamin Haley, Maxim Naumov, Faisal Saied, Marek Korkusinski, Rick Kennel, Michael Mclennan, Timothy B. Boykin, and Gerhard Klimeck, “Multimillion Atom Simulations with NEMO3D,” Encyclopedia of Complexity and Systems Science, Meyers, Robert (Ed.), vol. 6, pp. 5745–5783, Springer New York, 2009.

 

(C)  Scholarly and Academic Papers:

Peer-Reviewed Journals/Transactions/Reviews/Periodicals:

  1. Saad Mubarak Al-Qahtani, Muhammad Usman, and Shaikh Ahmed, “Unusual Bandgap Bowing in Highly Mismatched ZnOS Alloys: Atomistic Tight-Binding Band Anti-Crossing Model,” Journal of Applied Physics, accepted, 2019.

  2. Mohammad Rashid and Shaikh Ahmed, "Quantification of Phonon Boundary Scattering on Rough Surfaces: Employing B-K model in a Phonon Monte Carlo Simulator, " submitted 2019.

  3. Md. Rezaul Karim Nishat and Shaikh S. Ahmed, “Modeling and Tuning of Fine-Structure Splitting in Quantum Dot-in-Nanowire Structures for Quantum Key Distribution,” submitted 2019.

  4. Mayada M. Taher and Shaikh S. Ahmed, “Spacer Engineering Strategy for Hexagonal InGaN MQDs Nanowire Structure,” submitted 2019.

  5. Khadija A. Khair and Shaikh S. Ahmed, “Effects of Uniaxial and Biaxial Strain on Polar Optical Phonon Scattering and Electron Transport in Monolayer MoS2 FETs,” submitted 2019.

  6. Abdulmuin M. Abdullah, Md Rezaul Karim Nishat, and Shaikh S. Ahmed, “Multiscale-Multiphysics Modeling of Nonpolar InGaN/GaN Devices,” submitted 2019.

  7. Md. Rezaul Karim Nishat, Mayada M. Taher, and Shaikh S. Ahmed, “Million-Atom Tight-Binding Modeling of Nonpolar a-Plane InGaN Light Emitters, Journal of Computational Electronics, vol. 17, no. 4, pp. 1630–1639, 2018.

  8. Ye Wu, Zi-Chang Zhang, and Shaikh Ahmed, “First-Principles Investigation of Size-Dependent Piezoelectric Properties of Bare ZnO and ZnO/MgO Core-Shell Nanowires,” Superlattices and Microstructures, vol. 120, p. 732-737, 2018.

  9. Zi-Chang Zhang, Ye Wu, Chao Lu, and Shaikh Ahmed, “Electron Mobility in β-Ga2O3: Role of Polar Optical Phonon Scattering,” Applied Physics A, vol. 124, no. 9, pp. 637, 2018.

  10. Mayada Taher and Shaikh Ahmed, “III-Nitride Multiple Disk-in-Wire Laser Structures: Effects of Crystal Orientation and Spacer Size,” Optical Materials, vol. 83, pp. 104–110, 2018.

  11. Md Rezaul Karim Nishat, Saad M. Alqahtani, Vinay U. Chimalgi, Neerav Kharche, and Shaikh S. Ahmed, “Atomistic Modeling of Nonpolar m-Plane InGaN Disk-in-Wire Light Emitters,” Journal of Computational Electronics, vol. 16, no. 3, pp. 814–824, 2017.

  12. Saad Mubarak Al-Qahtani, Abdulmuin Abdullah, Md. Rezaul Karim Nishat and Shaikh Ahmed, “Diameter Dependent Polarization in ZnO/MgO Disk-in-Wire Emitters: Multiscale Modeling of Optical Quantum Efficiency,” Superlattices and Microstructures, vol. 103, pp. 48–55, 2017.

  13. Vinay Chimalgi, Md. R. K. Nishat, and Shaikh Ahmed, “Nonlinear Piezoelectricity and Efficiency Droop in Hexagonal In(Ga)N/GaN Disk-in-Wire LEDs,” Superlattices and Microstructures, vol. 84, pp. 91–98, 2015.

  14. Afsana Sharmin, Mohammad Rashid, Vamsi Gaddipati, Abu Sadeque, and Shaikh Ahmed, “Multiscale Design of Nanostructured Thermoelectric Coolers: Effects of Contact Resistances,” IEEE/TMS Journal of Electronic Materials, vol. 44, no. 6, pp. 1697–1703, 2015.

  15. Shaikh Ahmed, Sasi Sundaresan, Hoon Ryu, and Muhammad Usman, “Multimillion-Atom Modeling of InAs/GaAs Quantum Dots: Interplay of Geometry, Quantization, Atomicity, Strain, and Linear and Quadratic Polarization Fields,” Journal of Computational Electronics, vol. 14, pp. 543–556, 2015.

  16. Sasi Sundaresan, Vamsi Gaddipati, and Shaikh Ahmed, “Effects of Spontaneous and Piezoelectric Polarization Fields on the Electronic and Optical Properties in GaN/AlN Quantum Dots: Multimillion-Atom sp3d5s* Tight-Binding Simulations,” Int. J. Numer. Model., vol. 28, pp. 321–334, 2015.

  17. Vinay Chimalgi, Krishna Yalavarthi, Md Rezaul Karim Nishat, and Shaikh Ahmed, “Atomistic Simulation of Surface Passivated Wurtzite Nanowires: Electronic Bandstructure and Optical Emission,” Adv. Nano Research, vol. 2, no. 3, pp. 157–172, 2014.

  18. Vinay Chimalgi, Neerav Kharche, and Shaikh Ahmed, “Effects of Substrate Orientation on Opto-Electronic Properties in Self-Assembled InAs/GaAs Quantum Dots,” Journal of Computational Electronics, vol. 13, pp. 1026–1032, 2014.

  19. Krishna Yalavarthi, Vinay Chimalgi and Shaikh Ahmed, “How Important is Nonlinear Piezoelectricity in Wurtzite GaN/InN/GaN Disk-in-Nanowire LED Structures?” Optical and Quantum Electronics, vol. 46, pp. 925–933, 2014.

  20. Ky Merrill, Krishna Yalavarthi and Shaikh Ahmed, “Giant Growth-Plane Optical Anisotropy in c-Plane Wurtzite GaN/InN/GaN Dot-in-Nanowires,” Superlattices and Microstructures, vol. 52, no. 5, pp. 949–961, 2012.

  21. Muhammad Usman, Yui-Hong Matthias Tan, Hoon Ryu, Shaikh S Ahmed, Hubert J Krenner, Timothy B Boykin and Gerhard Klimeck, “Quantitative Excited State Spectroscopy of a Single InGaAs Quantum Dot Molecule through Multi-Million Atom Electronic Structure Calculations,” Nanotechnology, vol. 22, 315709, 2011.

  22. Krishna Yalavarthi, Vamsi Gaddipati, and Shaikh Ahmed, “Internal Fields in InN/GaN Quantum Dots: Geometry Dependence and Competing Effects on the Electronic Structure,” Physica E: Low-Dimensional Systems and Nanostructures, vol. 43, pp. 1235–1239, 2011.

  23. S. Ahmed, C. Ringhofer, D. Vasileska, “An Effective Potential Approach for Modeling 25 nm MOSFET Devices,” Journal of Computational Electronics, vol. 9, no. 3, 197, 2010.

  24. Shaikh Ahmed, Sharnali Islam, and Shareef Mohammed, “Electronic Structure of InN/GaN Quantum Dots: Multimillion Atom Tight-Binding Simulations,” IEEE Trans. Electron Devices, vol. 57, no. 1, pp. 164–173, 2010.

  25. S. Li, S. Ahmed, E. Darve, and G. Klimeck, “Compute the Diagonal of Sparse Matrix Inverse using FIND Algorithm,” Journal of Computational Physics, vol. 227, pp. 9408–9427, 2008.

  26. Himadri S. Pal, Kurtis D. Cantley, Shaikh S. Ahmed, and Mark S. Lundstrom, “Influence of Bandstructure and Channel Structure on the Inversion Layer Capacitance of Silicon and GaAs MOSFETs,” IEEE Trans. Electron Devices, vol. 55, no. 3, pp. 904–908, 2008.

  27. D. Vasileska, H. Khan, and S. Ahmed, “Modeling Coulomb effects in nanoscale devices,” Journal of Computational and Theoretical Nanoscience, vol. 5, no. 9, pp. 1793–1827, September 2008.

  28.  Neophytos Neophytou, Shaikh Ahmed, Gerhard Klimeck, “Influence of vacancies on metallic nanotube transport performance,” Applied Physics Letter, vol. 90, 182119, 2007.

  29. Gerhard Klimeck, Shaikh Ahmed, Hansang Bae, Neerav Kharche, Rajib Rahman, Steve Clark, Benjamin Haley, Sunhee Lee, Maxim Naumov, Hoon Ryu, Faisal Saied, Marta Prada, Marek Korkusinski, and Timothy B. Boykin, “Atomistic Simulation of Realistically Sized Nanodevices Using NEMO 3-D—Part I: Models and Benchmarks,” IEEE Trans. Electron Devices, vol. 54, no. 9, pp. 2079–89, 2007.

  30. Gerhard Klimeck, Shaikh Ahmed, Neerav Kharche, Marek Korkusinski, Muhammad Usman, Marta Prada, and Timothy Boykin, “Atomistic Simulation of Realistically Sized Nanodevices Using NEMO 3-D—Part II: Applications,” IEEE Trans. Electron Devices, vol. 54, no. 9, pp. 2090–99, 2007.

  31. Neophytos Neophytou, Shaikh Ahmed, Gerhard Klimeck, “Non-Equilibrium Green’s Function (NEGF) Simulation of Metallic Carbon Nanotubes: The Effect of the Vacancy Defect,” Journal of Computational Electronics, vol. 6, no. 1–3, pp. 317–320, September 2007.

  32. C. Heitzinger, C. Ringhofer, S. Ahmed, and D. Vasileska, “3D Monte-Carlo Device Simulations Using an Effective Quantum Potential Including Electron-Electron Interactions,” Journal of Computational Electronics, vol. 6, no. 1–3, pp. 15–18, September 2007.

  33. S. Li, S. Ahmed, and E. Darve, “Fast Inverse using Nested Dissection for NEGF,” Journal of Computational Electronics, vol. 6, no. 1–3, pp. 187–190, September 2007.

  34. S. Ahmed, M. Usman, C. Heitzinger, R. Rahman, A. Schliwa, and G. Klimeck, “Symmetry Breaking and Fine Structure Splitting in Zincblende Quantum Dots: Atomistic Simulations of Long-Range Strain and Piezoelectric Field,” AIP Conference Proceedings, vol. 893, pp. 849–850, 2007.

  35. Muhammad Usman, Shaikh Ahmed, Marek Korkusinski, Clemens Heitzinger, and Gerhard Klimeck, “Strain and electronic structure interactions in realistically scaled quantum dot stacks,” AIP Conference Proceedings, vol. 893, pp. 847–848, 2007.

  36. Shaikh Ahmed, Gerhard Klimeck, Derrick Kearney, Michael McLennan, MP Anantram, “Quantum Simulations of Dual Gate MOSFET Devices: Building and Deploying Community Nanotechnology Software Tools on NanoHUB.org,” Int. Journal of High Speed Electronics, vol. 17, no. 3, pp. 485–494, 2007.

  37. AKM. Ahsan and S. Ahmed, “Impact of Halo Angle on 1/f noise in Conventional MOSFET technology,” Solid State Electronics, vol. 50, pp.1705–1709, 2006.

  38. Shaikh Ahmed, Christian Ringhofer, and Dragica Vasileska, “Parameter-Free Effective Potential Method for Use in Particle-Based Device Simulations,” IEEE Trans. Nanotechnology, vol. 4, no. 4, pp. 465–471, 2005.

  39. D. Vasileska and S. Ahmed, “Narrow-Width SOI Devices: The Role of Quantum Mechanical Size Quantization Effect and the Unintentional Doping on the Device Operation,” IEEE Trans. Electron Devices, vol. 52, no. 2, pp. 227–236, 2005.

  40. S. Ahmed, D. Vasileska and C. Ringhofer, “Quantum Potential Approach to Modeling Nanoscale MOSFETs,” Journal of Computational Electronics, vol. 4, no. 1, pp. 57–61, 2005.

  41. D. Vasileska, H. R. Khan and S. S. Ahmed, Christian Ringhofer, and Clemens Heitzinger “Quantum and Coulomb Effects in Nanodevices,” International Journal of Nanoscience, vol. 4, No. 3, pp. 305–361, 2005.

  42. J. Choi, S. Ahmed, T. Dimitrova, J. Chen, and D. K. Schroder, “The Role of the Mercury-Si Schottky-Barrier Height in ψ-MOSFETs,” IEEE Trans. Electron Devices, vol. 51, no. 7, pp. 1164–1168, 2004.

  43. K. Tarik, S. Ahmed, D. Vasileska and T.J. Thornton, “Subthreshold Mobility Extraction for SOI-MESFETs,” Journal of Computational Electronics, vol. 3, pp. 243–246, 2004.

  44. H. Khan, D. Vasileska, S. Ahmed, C. Heitzinger, and C. Ringhofer, “Modeling of FinFET: 3D MC Simulation Using FMM and Unintentional Doping Effects on Device Operation,” Journal of Computational Electronics, vol. 3, pp. 337–340, 2004.

  45. S. Ahmed and Dragica Vasileska, “Modeling narrow-width SOI devices,” Semiconductor Science and Technology, vol. 19, pp. 131–133, 2004.

  46. Dragica Vasileska and Shaikh Ahmed, “Monte Carlo Simulation of Narrow-Width SOI Devices: Incorporation of the Short-Range Coulomb Interaction,” Monte Carlo Methods and Applications, vol. 10, No. 3–4, pp. 629–640, 2004.

  47. Shaikh S. Ahmed, Dragica Vasileska, “Modeling Narrow-Width SOI Devices: The Role of Quantum Mechanical Narrow Channel Effects on Device Performance,” Lecture Notes in Computer Science, vol. 2907, pp. 105–111, 2004.

  48. M. Nedjalkov, S. Ahmed, and D. Vasileska, “A self-consistent event biasing scheme for statistical enhancement,” Journal of Computational Electronics, vol. 3, pp. 305–309, 2004.

  49. S. Ahmed, C. Ringhofer, and D. Vasileska, “Effective potential approach for modeling MOSFET devices,” Journal of Computational Electronics, vol. 2, pp. 113–117, 2003.

  50. S. Ahmed and D. Vasileska, “Threshold voltage shifts in narrow-width SOI devices due to quantum mechanical size-quantization effects,” Physica E: Low-Dimensional Systems and Nanostructures, vol. 19, pp. 48–52, 2003.

  51. C. Ringhofer, S. Ahmed, and D. Vasileska, “Effective potential approach to modeling of 25 nm MOSFET devices,” Superlattices and Microstructures, vol. 34, pp. 311–317, 2003.

  52. D. Vasileska, R. Akis, I. Knezevic, S. N. Milicic, Shaikh S. Ahmed, and D. K. Ferry, “The role of quantization effects in the operation of ultrasmall MOSFETs and SOI devices,” Microelectronic Engineering, vol. 63, pp. 233–237, 2002.

  53. D. Vasileska, I. Knezevic, R. Akis, S. Ahmed, and D. K. Ferry, “The Role of Quantum Effects on the Operation of 50 nm MOSFETs, 250 nm FIBMOS Devices and Narrow-Width SOI Device Structures,” Journal of Computational Electronics, vol. 1, pp. 453–457, 2002.

Peer-Reviewed/Refereed Proceedings Archived by IEEE:

  1. Khadija A. Khair and Shaikh S. Ahmed, “Role of Interfacial and Intrinsic Coulomb Impurities in Monolayer MoS2 FETs,” IEEE-NMDC 2018, Proc. of 13th Nanotechnology Materials & Devices Conference, pp. 1–4, 2018.

  2. Saad M. Alqahtani and Shaikh S. Ahmed, “Valence Band Anti-Crossing Analysis of Dilute Sulfur in ZnO1-xSx Alloys,” IEEE-NMDC 2018, Proc. of 13th Nanotechnology Materials & Devices Conference, pp. 1–4, 2018.

  3. Mohammad Z. Rashid and Shaikh S. Ahmed, “Lattice Thermal Conductivity Reduction Due to Diffusive Boundary Scattering in Nanowires,” IEEE-NMDC 2018, Proc. of 13th Nanotechnology Materials & Devices Conference, pp. 1–4, 2018.

  4. Zi-Chang Zhang, Ye Wu, Chao Lu and Shaikh S. Ahmed, “Electronic Structure and Carrier Transport Analysis in β-Ga2O3 Using a Two-Valley Ensemble Monte Carlo Framework,” IEEE-NMDC 2018, Proc. of 13th Nanotechnology Materials & Devices Conference, pp. 1–4, 2018.

  5. Md Rezaul Karim Nishat, Archana Tankasala, Kharche Neerav, Rajib Rahman, and Shaikh Ahmed, “Multiscale-Multiphysics Modeling of Nonpolar InGaN LEDs,” IEEE-NANO 2017, Proc. of 17th IEEE Conference on Nanotechnology, pp. 85–88, 2017.

  6. Khadija Khair and Shaikh Ahmed, “Effects of Uniaxial Strain on Polar Optical Phonon Scattering and Electron Transport in Monolayer MoS2 FETs,” IEEE-NANO 2017, Proc. of 17th IEEE Conference on Nanotechnology, pp. 246–249, 2017.

  7. Abdulmuin M. Abdullah, Md Rezaul Karim Nishat, Shaikh Ahmed, “Atomistic Simulation of III-Nitride Core-Shell QD Solar Cells,” IEEE-NANO 2017, Proc. of 17th IEEE Conference on Nanotechnology, pp. 155–158, 2017.

  8. Shaikh Ahmed, Mohammad Rashid, Saad Al-Qahtani, Md Rezaul Karim Nishat, Khadija Khair, Ye Wu, Abdussamad Muntahi, Mayada Taher and Abdulmuin Abdullah, “Multiscale and Multiphysics Modeling of Non-Classical Semiconductor Devices,” ICECE 2016, Proc. of 9th Int. Conference on Electrical and Computer Engineering, Dhaka, Bangladesh, December 2016. (DOI:10.1109/ICECE.2016.7853846; http://ieeexplore.ieee.org/document/7853846/)

  9. Jaime Bohorquez-Ballen, Hansika Sirikumara, Shaikh Ahmed, Thushari Jayasekera, “Lattice vibrational properties of Si/Ge core-shell nanowires for thermoelectric applications,” IWCE 2015, Proc. of 18th International Workshop on Computational Electronics 2015, West Lafayette, IN, USA, pp. 1-4, 2-4 Sept. 2015. (DOI:10.1109/IWCE.2015.7301984; http://ieeexplore.ieee.org/document/7301984/)

  10. Md. R. Nishat, S. Alqahtani, Y. Wu, V. Chimalgi, and S. Ahmed, “GaN/InGaN/GaN Disk-in-Wire Light Emitters: Polar vs. Nonpolar Orientations,” IWCE 2015, Proc. of 18th International Workshop on Computational Electronics 2015, West Lafayette, IN, USA, pp. 1-2, 2-4 Sept. 2015. (DOI:10.1109/IWCE.2015.7301936; http://ieeexplore.ieee.org/document/7301936/)

  11. K. A. Khair and S. S. Ahmed, “Diffusive Transport in Monolayer MoS2: Role of Remote Coulomb Scattering,” IWCE 2015, Proc. of 18th International Workshop on Computational Electronics 2015, West Lafayette, IN, USA, pp. 1-2, 2-4 Sept. 2015. (DOI:10.1109/IWCE.2015.7301937; http://ieeexplore.ieee.org/document/7301937/

  12. M. Rashid, S. Sundaresan, T. Jayasekera and S. Ahmed, “VFF-Monte Carlo framework for phonon transport in nanostructures,” IWCE 2015, Proc. of 18th International Workshop on Computational Electronics 2015, West Lafayette, IN, USA, pp. 1-2, 2-4 Sept. 2015. (DOI:10.1109/IWCE.2015.7301935; http://ieeexplore.ieee.org/document/7301935/)

  13. Sasi Sundaresan, Krishna Yalavarthi, and Shaikh Ahmed, “Effects of atomicity and internal polarization on the electronic and optical properties of GaN/AlN quantum dots: Multimillion-atom coupled VFF MM- sp3d5s* tight-binding simulations,” IWCE 2012, Proc. of 15th International Workshop on Computational Electronics 2012, University of Wisconsin, Madison, Print ISBN: 978-1-4673-0705-5, May 1522, 2012.  (DOI:10.1109/IWCE.2012.6242864; http://ieeexplore.ieee.org/document/6242864/)

  14. Krishna Yalavarthi, Sasi Sundaresan, and Shaikh Ahmed, “Multiscale Modeling of Wurtzite InN/GaN Quantum Dot LEDs,” IEEE-NANO 2011, Proc. of 8th IEEE Conference on Nanotechnology, pp. 881–886, 2011. (DOI:10.1109/NANO.2011.6144420; http://ieeexplore.ieee.org/document/6144420/)

  15. Alejandra J. Magana, Dragica Vasileska, and Shaikh Ahmed, “A Transparency and Scaffolding Framework for Computational Simulation Tools,” FIE 2011, Proc. of 41st IEEE/ASEE Frontiers in Education Conference, Rapid City, SD, October 12–15, 2011. (DOI:10.1109/FIE.2011.6142803; http://ieeexplore.ieee.org/document/6142803/)

  16. Sasi Sundaresan, Sharnali Islam, and Shaikh Ahmed, “Built-In Electric Fields in InAs/GaAs Quantum Dots: Geometry Dependence and Effects on the Electronic Structure,” IEEE-NMDC 2010, Proc. of IEEE Nanotechnology Materials and Devices Conferences 2010, October 12–15, pp. 30–35, California, USA, 2010. (DOI:10.1109/NMDC.2010.5652313; http://ieeexplore.ieee.org/document/5652313/)

  17. Ramya Hindupur, Sharnali Islam, and Shaikh Ahmed, “Atomistic Modeling of Unintentional Single Charge Effects in Silicon Nanowire FETs,” IEEE-NMDC 2010, Proc. of IEEE Nanotechnology Materials and Devices Conferences 2010, pp. 282–285, California, USA, October 12–15, 2010. (DOI:10.1109/NMDC.2010.5652451; http://ieeexplore.ieee.org/document/5652451/)                            

  18. Muhammad Usman, Shaikh Ahmed, and Gerhard Klimeck, “A tight binding study of strain-reduced confinement potentials in identical and non-identical InAs/GaAs vertically stacked quantum dots,” IEEE-NANO 2008, Proc. of 8th IEEE Conference on Nanotechnology, pp. 541–544, Arlington, TX, USA, 2008. (DOI:10.1109/NANO.2008.161; http://ieeexplore.ieee.org/document/4617143/)

  19. Kurtis D. Cantley, Yang Liu, Himadri S. Pal, Tony Low, Shaikh S. Ahmed, and Mark S. Lundstrom, “Performance Analysis of III-V Materials in a Double-Gate nano-MOSFET,” IEDM 2007, Technical Digest of IEEE Int. Electron Device Meeting IEDM, Washington, DC, pp. 113–116, December 10–12, 2007. (DOI:10.1109/IEDM.2007.4418877; http://ieeexplore.ieee.org/document/4418877/)

  20. S. Ahmed, M. Usman, C. Heitzinger, R. Rahman, A. Schliwa, and G. Klimeck, “Atomistic Simulation of Non-Degeneracy and Optical Polarization Anisotropy in Pyramidal Quantum Dots,” IEEE-NEMS 2007, Proc. of the 2nd IEEE International Conference on Nano/Micro Engineered and Molecular Systems, pp. 937–942, January 16–19, 2007. (DOI:10.1109/NEMS.2007.352172; http://ieeexplore.ieee.org/abstract/document/4160475/)

  21. S. S. Ahmed, C. Ringhofer and D. Vasileska, “Efficacy of the thermalized effective potential approach for modeling nanodevices,” SISPAD 2005, Proc. of the International Conference on Simulation of Semiconductor Processes and Devices 2005, pp. 251–254, 2005. (DOI:10.1109/SISPAD.2005.201520; http://ieeexplore.ieee.org/document/1562072/)

  22. S. S. Ahmed, and D. Vasileska, “Modeling of Narrow-Width SOI Devices: The Impact of Quantum Mechanical Size Quantization Effects and Unintentional Doping on Device Operation”, DRC 2004, Technical Digest of the 62nd Device Research Conference, pp. 117–118, University of Notre Dame, Indiana, USA, June 21–23, 2004. (DOI:10.1109/DRC.2004.1367811; http://ieeexplore.ieee.org/document/1367811/)

  23. D. Vasileska and S. Ahmed, “How Quantum Effects and Unintentional Doping Affect the Threshold Voltage of Narrow-Width SO1 Devices,” IEEE-NANO 2004, Proc. of 4th IEEE Conference on Nanotechnology, pp. 340–42, 2004. (DOI:10.1109/NANO.2004.1392344; http://ieeexplore.ieee.org/document/1392344/)

  24. S. Ahmed and D. Vasileska, “Narrow-Width SOI Devices: The Role of Quantum Mechanical Space-Quantization Effects on Device Performance,” IEEE-NANO 2002, Proc. of 2002 IEEE Conference on Nanotechnology, pp. 243–246, 2002. (DOI:10.1109/NANO.2002.1032238; http://ieeexplore.ieee.org/document/1032238/)

Other Refereed Conference Proceedings:

  1. Krishna Yalavarthi, Vinay Chimalgi, Sasi Sundaresan and Shaikh Ahmed, “Modeling InGaN Disk-in-Wire LEDs: Interplay of Quantum Atomicity and Structural Fields,” SISPAD 2012, Proc. of The 2012 International Conference on Simulation of Semiconductor Processes and Devices, Denver, Colorado, USA, pp. 221–224, September 5-7, 2012. (http://in4.iue.tuwien.ac.at/pdfs/sispad2012/12-1.pdf)

  2. Mumba, M. Zhu, J. Ma and S. Ahmed, “New Design and Implementation of a Virtual Classroom System Using Google App Engine,” SITE 2012, Proc. of Society for Information Technology & Teacher Education International Conference, P. Resta (Ed.), pp. 698-705, Chesapeake, VA: Association for the Advancement of Computing in Education (AACE). (https://www.learntechlib.org/p/39653)

  3. Krishna Yalavarthi, Vamsi Gaddipati, and Shaikh Ahmed, “Atomistic Simulations of Electronic Structure in Realistically-Sized Wurtzite InN/GaN Quantum Dots having Different Geometries,” NSTI-Nanotech 2010, Proc. of the 2010 NSTI Nanotechnology Conference, vol. 2, pp. 37–40, California, USA, June 21–24, 2010. (http://www.nsti.org/publications/Nanotech/2010/pdf/1623.pdf)

  4. H. Khan, S. S. Ahmed and D. Vasileska, “Examination of the effects of unintentional doping on the operation of FinFETs with Monte Carlo Simulation Integrated with fast multipole method,” NSTI-Nanotech 2005, Proc. of the 2005 NSTI Nanotechnology Conference, vol. 3, pp. 41–44, Anaheim, CA, USA, 2005. (http://www.nsti.org/publications/Nanotech/2005/pdf/702.pdf)

  5. S. Ahmed and D. Vasileska, “Threshold Voltage Shifts in Narrow-Width SOI Devices Due to Quantum Mechanical Size-Quantization Effects,” NSTI-Nanotech 2003, Proc. of the Nanotechnology Conference and Trade Show, vol. 2, pp. 222–225, Feb. 23–27, San Francisco, California, USA, 2003. (http://www.nsti.org/publications/Nanotech/2003/pdf/T3404.pdf)

  6. S. S. Ahmed, R. Akis and D. Vasileska, “Quantum Effects in SOI Devices,” NSTI-Nanotech 2002, Proc. of 2002 International Conference on Modeling and Simulation of Microsystems, vol. 1, pp. 518–521, San Juan, Puerto Rico, USA, April 22–25, 2002. (http://nsti.org/publications/MSM/2002/pdf/186.pdf)

Other Technical Writings:

  1. Dragica Vasileska, Katerina Raleeva, Stephen M. Goodnick, Christian Ringhofer, Shaikh S. Ahmed, Nabil Ashraf, Arif Hossain, Raghuraj Hathwar, Ashwin Ashok, Balaji Padmanabhan, “Monte Carlo Device Simulations,” In book: Monte Carlo Device Simulations, Chapter: Nanohub Resources on Monte Carlo Device Simulations Study, Editors: Nanohub Research Professionals, pp.1-76, October 2011. available at: http://www.nanohub.org/resources/10579/download.

  2. S. Sundaresan, K. Yalavarthi, V. Gaddipati, M. Usman, and S. Ahmed, “Effects of internal fields in self-assembled InN/GaN quantum dots: Multimillion-atom tight-binding simulations”, presented at ORNL Technical Workshop on Scientific Discovery through Advanced Computing (SciDAC), July 11–15, 2010, Chattanooga, Tennessee, USA.

  3. C. Heitzinger, S. Ahmed, C. Ringhofer, and D. Vasileska, “Accurate Three-Dimensional Simulation of Electron Mobility Including Electron-Electron and Electron-Dopant Interactions” available: https://math.la.asu.edu/~chris/ecs040831.pdf  (accessed 04/16/2017)

  4. C. Heitzinger, C. Ringhofer, S. Ahmed, and D. Vasileska, “On the Efficient Simulation of Electron-Electron Interactions in Nanoscale MOSFETs,” available: https://math.la.asu.edu/~chris/TNT-2004-Heitzinger.pdf (accessed 04/16/2017)

  5. Dragica Vasileska; Shaikh S. Ahmed; Gerhard Klimeck (2008), “Why QuaMC 2D and Particle-Based Device Simulators?,” https://nanohub.org/resources/4520

  6. Dragica Vasileska; Shaikh S. Ahmed; Gerhard Klimeck (2008), "Examples for QuaMC 2D particle-based device Simulator Tool,” https://nanohub.org/resources/4543

  7. Dragica Vasileska; Shaikh S. Ahmed; David K. Ferry (2008), "Modeling Coulomb Effects in Nanoscale Devices,” https://nanohub.org/resources/4437

  8. Dragica Vasileska; Shaikh S. Ahmed; Gerhard Klimeck (2008), "Particle-Based Device Simulators Description,” https://nanohub.org/resources/4443

 

(D) Presentations at Technical Conferences/Workshops/Seminar Series

(Several of these appearances resulted in proceedings, which are listed in the previous section)

  1. Saad M. Alqahtani and Shaikh S. Ahmed, "Design of Thin Film Solar Cells Using Lightly Alloyed ZnOS as a Buffer Layer," MTC Poster Session, SIU, December 2018.

  2. Mohammad Z. Rashid and Shaikh S. Ahmed, "Quantification of Phonon Boundary Scattering on Rough Surfaces: Employing B-K model in a Phonon Monte Carlo Simulator," MTC Poster Session, SIU, December 2018.

  3. Zi-Chang Zhang, Ye Wu, Chao Lu and Shaikh S. Ahmed, "Carrier Transport Analysis based on Particle-Based Monte Carlo Method in β-Ga2O3," MTC Poster Session, SIU, December 2018.

  4. Khadija A. Khair and Shaikh S. Ahmed, “Role of Interfacial and Intrinsic Coulomb Impurities in Monolayer MoS2 FETs,” IEEE-NMDC 2018, Portland, Oregon, USA on 14-17 October, 2018.

  5. Saad M. Alqahtani and Shaikh S. Ahmed, “Valence Band Anti-Crossing Analysis of Dilute Sulfur in ZnO1-xSx Alloys,” IEEE-NMDC 2018, Portland, Oregon, USA on 14-17 October, 2018.

  6. Mohammad Z. Rashid and Shaikh S. Ahmed, “Lattice Thermal Conductivity Reduction Due to Diffusive Boundary Scattering in Nanowires,” IEEE-NMDC 2018, Portland, Oregon, USA on 14-17 October, 2018.

  7. Zi-Chang Zhang, Ye Wu, Chao Lu and Shaikh S. Ahmed, ” Electronic Structure and Carrier Transport Analysis in β-Ga2O3 Using a Two-Valley Ensemble Monte Carlo Framework,” IEEE-NMDC 2018, Portland, Oregon, USA on 14-17 October, 2018.

  8. Md Rezaul Karim Nishat, Archana Tankasala, Kharche Neerav, Rajib Rahman, and Shaikh Ahmed, “Multiscale-Multiphysics Modeling of Nonpolar InGaN LEDs,” IEEE-NANO 2017, Pittsburgh, PA, USA, July 25-28, 2017.

  9. Khadija Khair and Shaikh Ahmed, “Effects of Uniaxial Strain on Polar Optical Phonon Scattering and Electron Transport in Monolayer MoS2 FETs,” IEEE-NANO 2017, Pittsburgh, PA, USA, July 25-28, 2017.

  10. Abdulmuin M. Abdullah, Md Rezaul Karim Nishat, Shaikh Ahmed, “Atomistic Simulation of III-Nitride Core-Shell QD Solar Cells,” IEEE-NANO 2017, Pittsburgh, PA, USA, July 25-28, 2017.

  11. Shaikh Ahmed, “QuADS 3-D for Green Photonics,” STC Workshop, University of Michigan Ann Arbor, May 22, 2017 (invited).

  12. Shaikh Ahmed, Mohammad Rashid, Saad Al-Qahtani, Md Rezaul Karim Nishat, Khadija Khair, Ye Wu, Abdussamad Muntahi, Mayada Taher and Abdulmuin Abdullah, “Multiscale and Multiphysics Modeling of Non-Classical Semiconductor Devices,” ICECE 2016, 9th International Conference on Electrical and Computer Engineering, Dhaka, Bangladesh, December 2016. (invited)

  13. Shaikh Ahmed, “Multiscale Modeling of Quantum and Coulomb Effects in More-Moore Devices,” Weekly Seminar Series, Nanoelectronic Materials Branch, Materials and Manufacturing Directorate, Air Force Research Laboratory, Dayton, OH, USA, 21 July 2016.

  14. Abdulmuin Abdullah, Saad Alqahtani, Md Rezaul Karim Nishat, Shaikh Ahmed, “Multiscale modeling of nanostructured ZnO based devices for optoelectronic applications: Dynamically-coupled structural fields, charge, and thermal transport processes,” APS March Meeting 2016, Baltimore, MD, USA. (poster presentation)

  15. Md. R. Nishat, S. Alqahtani, Ye Wu, V. Chimalgi, and S. Ahmed, “GaN/InGaN/GaN Disk-in-Wire Light Emitters: Polar vs. Nonpolar Orientations,” 18th International Workshop on Computational Electronics (IWCE), Purdue University, West Lafayette, Sep. 2-4, 2015 (oral presentation).

  16. K. A. Khair and S. S. Ahmed, “Diffusive Transport in Monolayer MoS2: Role of Remote Coulomb Scattering,” 18th International Workshop on Computational Electronics (IWCE), Purdue University, West Lafayette, Sep. 2-4, 2015 (poster presentation).

  17. S. Sundaresan, M. Rashid, T. Jayasekera and S. Ahmed, “VFF-Monte Carlo Framework for Phonon Transport in Nanostructures,” 18th International Workshop on Computational Electronics (IWCE), Purdue University, West Lafayette, Sep. 2-4, 2015 (poster presentation).

  18. Jaime Bohorquez-Ballen, Hansika Sirikumara, Shaikh Ahmed, Thushari Jayasekera, “Phonon Engineering of Si/Ge Core-Shell Nanowires for Thermoelectric Applications, “18th International Workshop on Computational Electronics (IWCE), Purdue University, West Lafayette, Sep. 2-4, 2015 (poster presentation).

  19. Shaikh Ahmed, “nanoHUB @ SIU: pedagogy and beyond,” 2nd nanoHUB User Conference 2015, West Lafayette, Indiana, August 31- September 1, 2015 (Invited).

  20. Shaikh Ahmed, “Nanoscale Device Discovery through Scientific Computing,” Engineering Science Seminar Series, SIU, November 19, 2014.

  21. Rezaul Nishat, Vinay Chimalgi, and Shaikh Ahmed, “Designing Nanostructured InGaN LEDs: Interplay of Quantum Atomicity, Non-linear Polarization, and Crystal Directionality,” International Conference on Superlattices, Nanostructures, and Nanodevices, ICSNN 2014, Savannah, GA, USA, August, 2014. (oral presentation)

  22. Vamsi M. Gaddipati and Shaikh S. Ahmed, “On the Reliability of Nanoscale Nitride HEMTs: Multiscale Modeling of the Effects of Structural Modifications,” International Conference on Superlattices, Nanostructures, and Nanodevices, ICSNN 2014, Savannah, GA, USA, August, 2014. (poster presentation)

  23. Sameer Al-Sibiani and Shaikh S. Ahmed, “Quantum-Corrected Monte Carlo Simulation of Nanoscale Enhancement-Mode Tri-Gate III-V MOSFETs,” International Conference on Superlattices, Nanostructures, and Nanodevices, ICSNN 2014, Savannah, GA, USA, August, 2014. (oral presentation)

  24. Abu Sadeque, Afsana Sharmin, Vamsi Gaddipati, and Shaikh Ahmed, “Multiscale Design of Nanostructured Thermoelectric Coolers: Effects of Contact Resistances,” International Conference on Thermoelectrics (ICT2014), Nashville, Tennessee, USA, July 610, 2014. (poster presentation)

  25. Sasi Sundaresan, Abu Sadeque, Thushari Jayasekera, and Shaikh Ahmed, “Full-band phonon transport in nanostructures: A coupled molecular mechanics-Monte Carlo (MM-MC) approach,” International Conference on Thermoelectrics (ICT2014), Nashville, Tennessee, USA, July 610, 2014. (oral presentation)

  26. Jaime Bohorquez-Ballen, Masoud Babaeian, Micheal B. Ontl, Thushari Jayasekera, Sasi Sundaresan, Shaikh Ahmed, “Phonon engineering of Si/Ge core-shell nanowires for thermoelectric applications: Coherent model and beyond,” International Conference on Thermoelectrics (ICT2014), Nashville, Tennessee, USA, July 610, 2014. (oral presentation)

  27. Rezaul Nishat, Vinay Chimalgi, Krishna Yalavarthi, and Shaikh Ahmed, “Efficiency Droop in Nanostructured III-N LEDs: Multiscale Numerical Characterization and Design Optimization,” APS March Meeting 2014, Denver, Colorado, USA. (oral presentation)

  28. Sasi Sundaresan, Thushari Jayasekera, and Shaikh Ahmed, “Full-Band Particle-Based Monte-Carlo Simulation with Anharmonic Corrections for Phonon Transport in III-N Nanostructures,” APS March Meeting 2014, Denver, Colorado, USA. (poster presentation)

  29. Afsana Sharmin, Abu Sadeque, Vamsi Gaddipati, and Shaikh Ahmed, “Effects of Contact Resistances in Determining the Efficiency of Nanostructured Thermoelectric Coolers,” APS March Meeting 2014, Denver, Colorado, USA. (poster presentation)

  30. Sameer Al-Sibiani, Khadija Khair, and Shaikh Ahmed, “Modeling Quantum and Coulomb Effects in Nanoscale Enhancement-Mode Tri-Gate III-V MOSFETs,” APS March Meeting 2014, Denver, Colorado, USA. (oral presentation)

  31. Vinay Chimalgi and Shaikh Ahmed, “Atomistic Simulation of Electronic and Optical Properties of (100), (110) and (111) Oriented InAs/GaAs Quantum Dots,” APS March Meeting 2014, Denver, Colorado, USA. (poster presentation)

  32. Abdussamad Muntahi, Sameer Al-Sibiani, and Shaikh Ahmed, “Nanoscale Effects in Junctionless FETs,” APS March Meeting 2014, Denver, Colorado, USA. (poster presentation)

  33. Shaikh Ahmed, “More-than-Moore: Device Discovery and Design through Scientific Computing,” MTC Seminar Series, SIU, August 30, 2013.

  34. Krishna Yalavarthi, Sasi Sundaresan, Vinay Chimalgi and Shaikh Ahmed, “Atomistic Modeling of Electrical and Optical Characteristics of InGaN/GaN Disk-in-Wire LEDs,” SISPAD 2012, September 5-7, 2012, Denver, CO, USA, 2012. (acceptance rate ~57%) (oral presentation)

  35. Matthew Lane, Bradley Wrage, Shaikh Ahmed, Jun Qin, Tsuchin Chu, “Turbine Bearing-Seal Project,” NSF IUCRC seminar, O’Fallon, IL, June 12, 2012. (oral presentation)

  36. K. Khair, J. Ogden, and S. Ahmed, “Modeling Random Dopant Fluctuation Effects in Nanoscale Tri-Gate MOSFETs,” 15th International Workshop on Computational Electronics (IWCE), University of Wisconsin, Madison, May 2215, 2012. (poster presentation)

  37. S. Sundaresan, K. Yalavarthi, and S. Ahmed, “Competing Effects of Piezoelectric and Pyroelectric Polarization in GaN/AlN Quantum Dots: Multimillion-Atom sp3d5s* Tight-Binding Simulations,” 15th International Workshop on Computational Electronics (IWCE), University of Wisconsin, Madison, May 2215, 2012. (oral presentation)

  38. Matthew Lane, Bradley Wrage, Shaikh Ahmed, Jun Qin, Tsuchin Chu, “Turbine Bearing-Seal Project,” NSF IUCRC seminar, Tempe, AZ, January 26, 2012. (oral presentation)

  39. Mumba, M. Zhu, J. Ma and S. Ahmed, “New Design and Implementation of a Virtual Classroom System Using Google App Engine,” SITE 2012 Society for Information Technology & Teacher Education International Conference, Austin, Texas, USA; March 5-9, 2012.

  40. Krishna Yalavarthi, Sasi Sundaresan, Ky Merrill, and Shaikh Ahmed, “Effects of Internal Fields on the Optical Emission in Nanostructured III-N LEDs,” APS March Meeting 2012, Boston, MA. (oral presentation)

  41. Yashavanth Gowda, Sasi Sundaresan, Krishna Yalavarthi, and Shaikh Ahmed, “Engineering Efficiency Droop in InGaN/GaN Multiple Quantum Well LEDs,” APS March Meeting 2012, Boston, MA. (oral presentation)

  42. Joshua Ogden, Abdussamad Muntahi, Krishna Yalavarthi, and Shaikh Ahmed, “Modeling Random Dopant Fluctuation Effects in Nanoscale Tri-Gate MOSFETs,” APS March Meeting 2012, Boston, MA. (poster presentation)

  43. Vamsi Gaddipati, Sasi Sundaresan, Krishna Yalavarthi, and Shaikh Ahmed, “Atomistic Modeling of Degradation Mechanisms in Nanoscale HEMT Devices,” APS March Meeting 2012, Boston, MA. (poster presentation)

  44. Krishna Yalavarthi, Sasi Sundaresan, and Shaikh Ahmed,” Multiscale Modeling of Wurtzite InN/GaN Quantum Dot LEDs,” IEEE Conference on Nanotechnology IEEE NANO 2011, Aug 15–19, 2011, Portland, OR. (oral presentation)

  45. Shaikh Ahmed, “Atomistic Modeling of Degradation Mechanisms in Nitirde HEMTs,” NSF IUCRC seminar, June 2, 2011.

  46. Alejandra J. Magana, Dragica Vasileska, and Shaikh Ahmed, “A Transparency and Scaffolding Framework for Computational Simulation Tools,” 41st ASEE/IEEE Frontiers in Education Conference, October 12–15, 2011, Rapid City, SD.

  47. Shaikh Ahmed, “Nonclassical Nanoelectronics: Device Discovery and Design through Advanced Scientific Computation,” Key note lecture at Engineering Week, Southeast Missouri State University (SEMO), February 23, 2011.

  48. Shaikh Ahmed, “Multimillion-Atom Modeling of Nanoscale Devices for Applications in Harsh Environments,” Oak Ridge National Lab, TN, Feb 2011. (oral presentation)

  49. S. Sundaresan, K. Yalavarthi, V. Gaddipati, M. Usman, and S. Ahmed, “Effects of internal fields in self-assembled InN/GaN quantum dots: Multimillion-atom tight-binding simulations,” 2010 Scientific Discovery through Advanced Computing (SciDAC) Conference, July 11–15, 2010, The Chattanoogan Hotel and Conference Center, Chattanooga, Tennessee, USA. 

  50. Krishna Yalavarthi, Vamsi Gaddipati, and Shaikh Ahmed, “Atomistic Simulations of Electronic Structure in Realistically-Sized Wurtzite InN/GaN Quantum Dots having Different Geometries,” 2010 NSTI Nanotechnology Conference, Anaheim, California, June 21-24, 2010.

  51. Shaikh Ahmed, “nanoHUB@SIUC”, key note speaker at the NCN Workshop on Simulation-based Learning, Chicago, IL, November 2009.

  52. Hoon Ryu, Muhammad Usman, Shaikh Ahmed and Gerhard Klimeck, “Atomistic tight binding study of interband light transitions in self-assembled InAs/GaAs quantum dots,” MRS Fall Meeting, Boston, Dec. 1–4, 2008.

  53. Muhammad Usman, Shaikh Ahmed, and Gerhard Klimeck, “Atomistic tight binding study of strain-reduced confinement potentials in identical and non-identical InAs/GaAs vertically stacked quantum dots,” 8th IEEE Conference on Nanotechnology (NANO '08) Aug. 18–21 2008.

  54. Muhammad Usman, Shaikh Ahmed, and Gerhard Klimeck, “Strain and Piezoelectric Effects on the Electronic Structure of Coupled InxGa1-xAs/GaAs Self-Assembled Quantum Dots,” APS march meeting 2008, New Orleans, LA, USA.

  55. Shaikh Ahmed, “Quantum atomistic device simulations,” engineering seminar, SIUC, 2008.

  56. Shaikh Ahmed, “Parameter variations in nanoscale devices,” NSF I/UCRC seminar, St. Luis, December 2007.

  57. Roksana Golizadeh-Mojarad, A.N.M. Zainuddin, Shaikh S. Ahmed, Gerhard Klimeck, Supriyo Datta, “Atomistic NEGF Simulations of Carbon Nano-Ribbons in Magnetic Fields,” IWCE, Univ. Massachusetts at Amherst, 2007.

  58. Kurtis D. Cantley, Yang Liu, Himadri S. Pal, Tony Low, Shaikh S. Ahmed, and Mark S. Lundstrom, “Performance Analysis of III-V Materials in a Double-Gate nano-MOSFET,” IEDM, December 10–12, 2007, Hilton Washington, Washington, DC.

  59. S. Ahmed, M. Usman, C. Heitzinger, R. Rahman, A. Schliwa, and G. Klimeck, “Atomistic Simulation of Non-Degeneracy and Optical Polarization Anisotropy in Zincblende Quantum Dots,” 2nd IEEE Conference on Nano/Micro Engineered Molecular Systems, Bangkok, Thailand, 2007.

  60. Neophytos Neophytou, Shaikh Ahmed, Diego Kienle, Mark Lundstrom, Gerhard Klimeck, “Building and Deploying Community Nanotechnology Software Tools on nanoHUB.org – Non-Equilibrium Green's Function Simulations of the Impact of Atomic Defects on the Performance of Carbon Nanotube Transistors”, 2006 APS March Meeting, March 13–17, 2006, Baltimore, MD, USA.

  61. Gerhard Klimeck, Shaikh Ahmed, Marek Korkusiniski, Seungwon Lee, Faisal Saied, “Atomistic Simulations of Long-Range Strain and Close-Range Electronic Structure in Self-Assembled Quantum Dot Systems,” 2006 APS March Meeting, March 13–17, Baltimore, MD, USA.

  62. Shaikh Ahmed, Dragica Vasileska, Gerhard Klimeck, Christian Ringhofer, “Efficacy of the Thermalized Quantum Potential Approach for Modeling Nanoscale Semiconductor Devices,” 2006 APS March Meeting, March 13–17, Baltimore, MD, USA.

  63. Shaikh Ahmed, M. P. Anantram, Neophytos Neophytou, Marek Korkusinski, Gerhard Klimeck, “Quantum Simulations of Electronic Structure and Transport Properties in Conventional and Novel Nanoscale Devices,” 7th World Congress on Computational Mechanics, Los Angeles 2006.

  64. Neophytos Neophytou, Shaikh Ahmed, M.P. Anantram, and Gerhard Klimeck, "Non-Equilibrium Green's Function (NEGF) Simulation of Metallic Carbon Nanotube Transistors: Impact of Vacancy Defect,” 11th International Workshop on Computational Electronics (IWCE 11), Vienna, Austria, 2006.

  65. Shaikh Ahmed, Muhammad Usman, Clemens Heitzinger, Rajib Rahman, Andrei Schliwa, and Gerhard Klimeck “Symmetry breaking and fine structure splitting in self-assembled zincblende quantum dots: atomistic simulations of long-range strain and piezoelectric field,” 28th International Conference on the Physics of Semiconductors, ICPS, Vienna, Austria, July 24–28, 2006.

  66. Muhammad Usman, Shaikh Ahmed, Marek Korkusinski, Clemens Heitzinger, and Gerhard Klimeck, "Strain and electronic structure interactions in realistically scaled quantum dot stacks,” 28th International Conference on the Physics of Semiconductors, ICPS, Vienna, Austria, July 24–28 2006.

  67. Gerhard Klimeck, Rick Kennel, Michael McLennan, Stephen Clark, Clemens Heitzinger, Shaikh S. Ahmed, Wei Qiao, David Ebert, Sebastien Goasguen, Krishna Madhavan, “nanoHUB.org – A fully operational Science Gateway for the nano Science Community,” 2nd IEEE/ACM International Workshop on High Performance Computing for Nano-science and Technology (HPCNano06), Nov. 13, 2006, Tampa, Florida, USA.

  68. Michael McLennan, Sebastien Goasguen, Krishna Madhavan, Derrick Kearney, Joe Cychosz, Alicia Goodman, Shaikh Ahmed, Swaroop Shivarajapura, Shawn Rice, Carol Song, Steve Clark, Rick Kennel, Clemens Heitzinger, Mark Lundstrom, Gerhard Klimeck, “The nanoHUB—Online simulations and a community for nano-science and nano-technology,” Teragrid 2006, Indianapolis, IN June 12–15, 2006.

  69. Gerhard Klimeck, Shaikh Ahmed, Clemens Heitzinger, Neerav Kharche, Muhammad Usman, Mathieu Luisier, Raesong Kim, Neophytos Neophytou, Michael McLennan, and Timothy Boykin, “Quantum Dot, Nanowire, and Bandstructure Modeling, and Deployment on Nanohub.Org,” Int. Workshop Tera- and Nano- Devices: Physics and Modeling, October 16–19, 2006, Aizu, Japan.

  70. C. Heitzinger, C. Ringhofer, S. S. Ahmed and D. Vasileska, “3D Monte Carlo device simulations using an effective quantum potential including electron-electron interactions,” 11th International Workshop on Computational Electronics, IWCE, May 2006, Vienna, Austria.

  71. Shaikh S. Ahmed, “Building and Deploying Community Nanotechnology Software Tools on nanoHUB.org,” presentation at FreeScale vist at Purdue University, November 2005.

  72. Shaikh S. Ahmed, Marek Korkusinski, Faisal Saied, Haiying Xu, Seungwon Lee, Mohamed Sayeed, Sebastien Goasguen and Gerhard Klimeck, “Large Scale Simulation in Nanostructures with NEMO3-D on Linux Clusters,” 6th LCI International Conference on Linux Clusters: The HPC Revolution 2005, April 26–28, 2005, University of North Carolina, Chapel Hill, NC, USA.

  73. S. S. Ahmed, C. Ringhofer and D. Vasileska, “Efficacy of the thermalized effective potential approach for modeling nanodevices,” SISPAD 2005, Komaba Eminence, Tokyo, Japan, Sept. 1-3, 2005.

  74. Shaikh Ahmed, Gerhard Klimeck, Sebastien Goasguen, Faisal Saied, Marek Korkusinksi, Haiying Xu, and Seungwon Lee, “Building and Deploying Community Nanotechnology Software Tools on nanoHUB.org – Atomistic Simulations of Multimillion-Atom Quantum Dot Nanostructures,” I-light Symposium 2005, Indiana University, September 2005.

  75. Dragica Vasileska, Shaikh Ahmed, Christian Ringhofer, “Quantum Effects Incorporation into Monte Carlo Device Simulators for Modeling Nano-Scale Devices,” 2nd Annual Conference on Foundations of Nanoscience: Self-Assembled Architectures and Devices (Fnano05), Snowbird Cliff Lodge, Snowbird, UT, April 24 –28, 2005.

  76. Khan, S.S. Ahmed, D. Vasileska, “Examination of the Effects of Unintentional Doping on the Operation of FinFETs with Monte Carlo Simulation Integrated with Fast Multipole Method (FMM),” 2005 NSTI Nanotech Conference & Trade Show, Anaheim, May 8–12, 2005.

  77. C. Heitzinger, S. Ahmed, C. Ringhofer, and D. Vasileska, “Efficient Simulation of the Full Coulomb Interaction in Three Dimensions,” 9th International Workshop on Computational Electronics (IWCE 10), Purdue University, 2004.

  78. C. Heitzinger, S. Ahmed, C. Ringhofer, and D. Vasileska, “Accurate Three-Dimensional Simulation of Electron Mobility Including Electron-Electron and Electron-Dopant Interactions,” 206th Meeting of the Electrochem. Soc. ECS, October 2004, Honolulu, HI, USA.

  79. D. Vasileska and S. Ahmed, “Coulomb Effects on Nanoscale MOSFET Operation,” 4th IEEE Conference on Nanotechnology, August 17–19, 2004, Munich, Germany.

  80. S. S. Ahmed, and D. Vasileska, “Modeling of Narrow-Width SOI Devices: The Impact of Quantum Mechanical Size Quantization Effects and Unintentional Doping on Device Operation,” 62nd Device Research Conference DRC, University of Notre Dame, Indiana, USA, June 21–23, 2004.

  81. C. Heitzinger, C. Ringhofer, S. Ahmed, and D. Vasileska, “On the Efficient Simulation of Electron-Electron Interactions in Nanoscale MOSFETs,” Trends in Nanotechnology, TNT September 13–17, 2004, Segovia, Spain.

  82. T. Khan, S. Ahmed, T. Thornton, D. Vasileska, “Subthreshold mobility modeling of SOI MESFETs,” 10th International Workshop on Computational Electronics IWCE 2004, Purdue University, West Lafayette, USA, October 2004.

  83. S. Ahmed and D. Vasileska, “Threshold voltage shifts in narrow-width SOI devices due to quantum mechanical size-quantization effects,” Nanotechnology Conference and Trade Show, San Fransisco, California, USA, Feb. 23–27, 2003.

  84. S. Ahmed and D. Vasileska, “Modeling of narrow-width SOI devices: The role of quantum mechanical narrow channel effects on device performance,” 4th International Conference on Large-Scale Scientific Computations, June 4-8, 2003, Sozopol, Bulgaria.

  85. S. Ahmed, C. Ringhofer, and D. Vasileska, “Quantum potential for use in particle based simulations,” 9th Int. Workshop on Computational Electronics (IWCE 9), 25–28 May 2003, Italy.

  86. C. Ringhofer, D. Vasileska, S. Ahmed, “A thermodynamic quantum potential approach,” Workshop on Quantum and Many-Body Effects in Nanoscale Devices, Arizona State University, Tempe, Arizona, October 24–25, 2003. 

  87. S. Ahmed and D. Vasileska, “Modeling of narrow-width SOI devices,” 13th International Conference on Nonequilibrium Carrier Dynamics in Semiconductors (HCIS-13), July 28–August 01, 2003, Italy.

  88. S. Ahmed and D. Vasileska, “The Influence of Unintentional Doping on nanoscale MOSFET Operation,” 4th IMACS Seminar on Monte Carlo Methods, 15–19 Sep. 2003, Berlin, Germany.  

  89. S. Ahmed and D. Vasileska, “Quantum effects in narrow-width SOI devices,” 14th Workshop on Modeling and Simulation of Electron Devices, 16-17 October, Barcelona, Spain, 2003.

  90. S. S. Ahmed, and D. Vasileska, “Quantum mechanical narrow-channel effect in SOI devices,” 4th Int. Symposium on Nanostructures and Mesoscopic Systems (NanoMes), Tempe Mission Palms Hotel, Tempe, Arizona, USA, February 17–21, 2003.

  91. S. Ahmed, C. Ringhofer, and D. Vasileska, “Effective potential approach to modeling of 25 nm MOSFET devices,” 6th International Conference on New Phenomena in Mesoscopic Systems (NPMS-6) and Fourth International Conference on Surfaces and Interfaces of Mesoscopic Devices (SIMD-4), Maui, Hawaii, USA, December 1–5, 2003.

  92. S. S. Ahmed, and D. Vasileska, “Narrow-Width SOI Devices: The role of Quantum Mechanical Space-Quantization Effects on Device Performance,” 2nd IEEE Conference on Nanotechnology, Arlington, VA, USA, August 26–28, 2002. 

  93. S. S. Ahmed, R. Akis and D. Vasileska, “Modeling of Narrow-Width SOI devices,” 2002 IEEE Si Nanoelectronics Workshop, Honolulu, Hawaii, USA, June 9–10, 2002.

  94. S. S. Ahmed, R. Akis and D. Vasileska, “Quantum Effects in SOI Devices: A Scattering matrix calculation based on Landauer’s formalism,” 4th International Conference on Modeling and Simulation of Microsystems, San Juan, Puerto Rico, USA, April 22–25, 2002.

 


DESCRIPTION OF NANOELECTRONIC SOFTWARE  DEVELOPED  ///


Based on the research done over the past decade, it has been well-acknowledged and proven that simulation is an important research methodology in the fields of nanoscience and nanoengineering, and it is possible to accelerate the transformation of nanoscience to nanotechnology/nanosystems through the integration of simulation with experimentation. However, simulator development itself is not enough—the tools need to be deployed to the user community so that it can be made more flexible and accurate. With that vision, since 2002, the NSF through its science cyberinfrastructure nanoHUB.org has been offering a set of cyber services including interactive online simulation, tutorials, seminars, and online courses packaged using e-learning standards. All the services are freely open to the public. We have co-authored 12 nanoelectronics software (namely: nanoFET, CNTFET, QuaMC 2D, Schred, nanoMOS, FETtoy, MOSFET, MOScap, QPC, multiTEC, and nanoSSL) that are freely available on NSF’s nanoHUB.org.

Here is a short description of the the software that are freely available on nanoHUB.org.

  1. nanoFET simulates ballistic transport properties in two-dimensional classical and novel MOSFET devices. The overall F90 & C++ simulation framework consists of the non-equilibrium Green’s function equations solved self-consistently with Poisson’s equation. Four different algorithms have been employed ― (1) Recursive Green’s function, RGF (2) Fast Inverse using Nested Dissection, FIND (3) A parallel RGF solver, PDIV and (4) another parallel RGF solver in F90, SPIKE. A friendly GUI based on Rappture is provided. The simulations are freely available on NanoHUB.org.

  2. CNTFET can currently simulate the impact of quantum mechanical size quantization and phase coherence in zigzag carbon nanotubes with both planar and coaxial exterior architectures. The package is based on non-equilibrium Greens’ function (NEGF) techniques using a pz-orbital nearest-neighbor tight binding. Full three-dimensional (3D) electrostatics has been captured by the Finite-Element-Method (FEM) of solving the Poisson Equation. Solution of this set of equations is computationally intensive. One can reduce the simulation time by using a mode-space approach instead of the real-space approach. By default the simulator solves for both electrons and holes. A friendly GUI based on Rappture is provided. The simulation is freely available on NanoHUB.org.

  3. QuaMC (pronounced as quam-see) is a quasi three-dimensional quantum-corrected diffusive semiclassical Monte Carlo transport simulator for conventional and non-conventional MOSFET devices. A parameter-free quantum field approach has been developed and utilized quite successfully in order to capture the size-quantization effects in nanoscale MOSFETs. The method is based on a perturbation theory around thermodynamic equilibrium and leads to a quantum field formalism in which the size of an electron depends upon its energy. Also in this simulator, the use of self-consistent event-biasing schemes for statistical enhancement in the Monte Carlo device simulations has been presented. The simulation is freely available on NanoHUB.org.

  4. FETToy calculates the ballistic I-V characteristics for a conventional MOSFETs, Nanowire MOSFETs and Carbon Nanotube MOSFETs. Only the lowest subband is considered, but it is readily modifiable to include multiple subbands.

  5. MOSCap Simulates the capacitance of bulk and dual gate capacitors for a variety of different device sizes, geometries, temperature and doping profiles.

  6. MOSFET Simulates the capacitance of bulk and SOI Field Effect Transistors (FETs) for a variety of different device sizes, geometries, temperature and doping profiles. Enables the visualization of various device characteristics such as Id-Vd and Id-Vg. MOSFET lab is based on the Padre simulation tool developed by Mark Pinto, R. Kent Smith, and Ashraful Alam at Bell Labs.

  7. nanoMOS 3.0 NanoMOS is a 2-D simulator for thin body (less than 5 nm), fully depleted, double-gated n-MOSFETs. A choice of five transport models is available (drift-diffusion, classical ballistic, energy transport, quantum ballistic, and quantum diffusive). The quantum transport models are based on mode-space method within an effective mass approximation. Scattering in the device can also be treated by a simple model that uses so-called Büttiker probes.

  8. Schred 2.0 Calculates the envelope wavefunctions and the corresponding bound-state energies in a typical MOS (Metal-Oxide-Semiconductor) or SOS (Semiconductor-Oxide-Semiconductor) structure and a typical SOI structure by solving self-consistently the one-dimensional (1D) Poisson equation and the 1D Schrodinger equation.

  9. QPC, written in Fortran 90, originally by Richard Akis of Arizona State University, Tempe, Arizona, calculates the conductance and associated wavefunctions for electron waves flowing through one or more quantum point contacts (QPCs), as a function of either bottom potential or magnetic field. It uses a transfer/scattering matrix approach to find the coefficients that enter the Landauer formula to calculate the conductance. The quantum point contact that has been implemented is based on a model suggested by Ando (T. Ando, "Quantum Point Contacts in Magnetic Fields", Phys. Rev. B, vol 44, pp 8017, 1991).

  10. MultiscaleTEC is a multiscale simulator for thermoelectric cooler devices, where the material parameters are obtained atomistically using a combination of molecular dynamics and tight-binding simulations and then used in the system level design.

  11. nanoSSL simulator allows one to study the electronic bandstructure and optical properties of wurtzite GaN/InN/GaN disk-in-wire structures. Using the simulator one can: (i) Explore the origin and nature of various built-in fields including crystal atomicity, strain fields, piezoelectric, and pyroelectric potentials; (ii) Quantify the role of these internal fields on the electronic bandstructure in terms of shift in energy levels and split (non-degeneracy) in the excited P states, and (iii) Demonstrate how the atomistically-calculated electronic structures lead to strongly suppressed optical transitions and pronounced growth-plane optical polarization anisotropy in these emerging reduced-dimensionality LEDs. 

  12. MCPT simulator calculates lattice thermal conductivity by solving Boltzmann Transport Equation (BTE) numerically using a particle-based Monte Carlo simulation. Monte Carlo based statistical approach to solve Boltzmann Transport Equation (BTE) has become a norm to investigate heat transport in semiconductors at sub-micron regime, owing to its ability to characterize realistically sized device geometries qualitatively. One of the primary issues with this technique is that the approach predominantly uses empirically fitted phonon dispersion relation as input to determine the properties of phonons so as to predict the thermal conductivity of specified material geometry. The empirically fitted dispersion relations assumes harmonic approximation thereby failing to account for thermal expansion, interaction of lattice waves, effect of strain on spring stiffness, and accurate phonon-phonon interaction. In this simulator, the phonon dispersion relation were calculated using a modified valence force-field model so that it can capture the effects of anharmonicity. Also, the effect of rough surfaces on thermal conductivity is treated by employing a fitting parameter that treats the roughness of the material surface.

 

 

sample worldwide simulator usage map

 


HONORS AND AWARDS  ///


  1. Air Force Research Lab (AFRL) Summer Faculty Fellowship, Wright-Patterson Base, OH, 2016

  2. DOE Oak Ridge National Lab High-Performance Computing (HPC) Award, 2009

  3. Dean Juh Wah Chen Outstanding Faculty Award 2013, SIU College of Engineering

  4. ECE Department Teacher of the Year 2014

  5. IEEE Senior Member 2013

  6. 1st Place, Physical Sciences, Research Town-Hall Meeting, Southern Illinois University, 2012

  7. Keynote speaker, Engineering Week, Southeast Missouri State University, 2011

  8. Research featured in nanotechweb.org on 8/12/2011, “Supercomputers model real-world quantum dot devices 'atom-by-atom'”

  9. Workshop featured in The Southern on 2/28/2011, “SIUC brings iPads to classrooms”

  10. 3rd Place, Physical Sciences, Research Town-Hall Meeting 2011, Southern Illinois University, 2011

  11. ECE KHN (eta kappa nu) Honor Society, 2010

  12. Keynote speaker at the NSF NCN Workshop on Simulation-based Learning, November 2009

  13. Recognized/featured in The Saluki Times (May 1, 2009) and The Southern Illinoisan (May 2, 2009) for the accomplishment in high-performance computing efforts at SIUC

  14. Graduate Tuition Scholarship, 2001–04, Arizona State University

  15. Sweden-Bangladesh Education Travel Grant 2001

  16. BUET Dean’s List Scholarship 1997-8

  17. BUET Merit Scholarship 1995-8

  18. Ministry of Education Merit Scholarship, Bangladesh, 1986-94

  19. Marquis Who's Who in the World® 2019

  20. Who's Who in Science and Engineering 2011-2012

  21. Who's Who in America 2007

  22. Who’s Who in Engineering Academia 2009

 

///   Last Updated: June 07, 2019. Copyright © 2007-2015 Shaikh Shahid Ahmed. All rights reserved. ///