Journal Publications
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20th century: Publish or perish

21st century: Produce or perish


  1. P. Sarangapani, Y. Chu, J. Charles, G. Klimeck, and T. Kubis, Band-tail Formation and Band-gap Narrowing Driven by Polar Optical Phonons and Charged Impurities in Atomically Resolved III-V Semiconductors and Nanodevices, Phys. Rev. Applied 12, 044045 (2019)

  2. D. Mejia, T. Kubis, and G. Klimeck, NemoViz: A visual interactive system for atomistic simulations design, accepted for Visualization in Engineering (2018)

  3. Y. Chu, P. Sarangapani, J. Charles, G. Klimeck, and T. Kubis, Explicit screening full band quantum transport model for semiconductor nanodevices, J. Appl. Phys. 123, 244501 (2018)

  4. P. Sarangapani, C. Weber, J. Chang, S. Cea, M. Povolotskyi, G. Klimeck, T. Kubis, Atomistic tight-binding study of contact resistivity in Si/SiGe PMOS Schottky contact, IEEE Trans. on Nanotech. 17, 968 (2018)

  5. P. Long, J. Huang, M. Povolotskyi, P. Sarangapani, G. Valencia-Zapata, T. Kubis, M. Rodwell, G. Klimeck, Atomistic Modeling trap-assisted tunneling in hole tunnel Field Effect Transistors, Journal of Applied Physics 123, 174504 (2018)

  6. J. Geng, P. Sarangapani, K.-C. Wang, E. Nelson, B. Browne, C. Wordelman, J. Charles, Y. Chu, T. Kubis, G. Klimeck, Quantitative Multi-Scale, Multi-Physics Quantum Transport Modeling of GaN-Based Light Emitting Diodes, Phys. Status Solidi A 215, 1700662 (2018)

  7. K.-C. Wang, T. K. Stanev, D. Valencia, J. Charles, A. Henning, V. K. Sangwan, A. Lahiri, D. Mejia, P. Sarangapani, M. Povolotskyi, A. Afzalian, J. Maassen, G. Klimeck, M. C. Hersam, L. J. Lauhon, N. P. Stern, and T. Kubis, Control of interlayer physics in 2H transition metal dichalcogenides, J. Appl. Phys. 122, 224302 (2017)

  8. S. Sadasivam, N. Ye, J. P. Feser, J. Charles, K. Miao, T. Kubis, and T. S. Fisher, Thermal transport across metal silicide-silicon interfaces: First-principles calculations and Green's function transport simulation, Phys. Rev. B 95, 085310 (2017)

  9. P. Long, J. Z. Huang, M. Povolotskyi, D. Verreck, J. Charles, T. Kubis, G. Klimeck, M. J. W. Rodwell, B. H. Calhoun, A tunnel FET design for high-current, 120mV operation, Electron Devices Meeting (IEDM) (2016)

  10. K. Miao, S. Sadasivam, J. Charles, G. Klimeck, T. S. Fisher, and T. Kubis, Büttiker probes for dissipative phonon quantum transport in semiconductor nanostructures, Appl. Phys. Lett. 108, 113107 (2016)

  11. T. Kubis, Y. He, R. Andrawis, and G. Klimeck, General Retarded Contact Self-energies in and beyond the Non-equilibrium Green’s Function Method, Journal of Physics: Conference Series, 696, 012019 (2016)

  12. Y. He, Y. Tan, Z. Jiang, M. Povolotskyi, G. Klimeck, and T. Kubis, Surface Passivation in Empirical Tight Binding, IEEE Trans. on Electron Devices 63, 954 (2016)

  13. J. Charles, P. Sarangapani, R. Golizadeh-Mojarad, R. Andrawis, D. Lemus, X. Guo, D. Mejia, J. E. Fonseca, M. Povolotskyi, T. Kubis, G. Klimeck, Incoherent transport in NEMO5: realistic and efficient scattering on phonons, J. Comput. Electron. 15, 1123 (2016)

  14. F. W. Chen, L. A. Jauregui, Y. Tan, M. Manfra, G. Klimeck, Y. P. Chen, and T. Kubis, In-surface confinement of topological insulator nanowire surface states, Appl. Phys. Lett.  107, 121605 (2015)

  15. Y. P. Tan, M. Povolotskyi, T. Kubis, T. Boykin, and G. Klimeck, Tight-binding analysis of Si and GaAs ultrathin bodies with subatomic resolution, Phys. Rev. B 92, 085301 (2015)

  16. Z. Jiang, Y. Lu, Y. Tan, Y. He, M. Povolotskyi, T. Kubis, A. Seabaugh, P. Fay, G. Klimeck, Quantum Transport in AlGaSb/InAs TFETs With Gate Field In-Line With Tunneling Direction, IEEE Trans. on Elec. Dev., 62, 2445, (2015).

  17. R. Vedula, S. Mehrotra, T. Kubis, M. Povolotskyi, G. Klimeck, and A. Strachan, Optimal Ge/SiGe nanofin geometries for hole mobility enhancement: technology limit from atomic simulation, J. Appl. Phys. 117, 174312 (2015)

  18. P. Sengupta, T. Kubis, Y. Tan, and G. Klimeck, Proximity induced ferromagnetism, superconductivity, and finite-size effects on the surface states of topological insulator nanostructures, accepted for J. Appl. Phys. 117, 044304 (2015)

  19. P. Y. Long, M. Povolotskyi, B. Novakovic, T. Kubis, G. Klimeck, and M. J. W. Rodwell, Design and Simulation of Two-Dimensional Superlattice Steep Transistors, IEEE Electron. Dev. Lett. 35, 1212 (2014).

  20. Y. He, Y. Wang, G. Klimeck, and T. Kubis, Non-equilibrium Green's Functions Method: Non-trivial and Disordered Leads, Appl. Phys. Lett. 105, 213502 (2014).

  21. G. Hedge, M. Povolotskyi, T. Kubis, J. Charles, G. Klimeck, An Environment-dependent Semi-Empirical Tight Binding Model Suitable for Electron Transport in Bulk Metals, Metal Alloys, Metallic Interfaces and Metallic Nanostructures II - Effect of Confinement and Homogeneous Strain on Cu Conductance, J. Appl. Phys. 115, 123703 (2014).

  22. G. Hedge, M. Povolotskyi, T. Kubis, J. Charles, and G. Klimeck, An Environment-dependent Semi-Empirical Tight Binding Model Suitable for Electron Transport in Bulk Metals, Metal Alloys, Metallic Interfaces and Metallic Nanostructures. I - Model and validation, J. Appl. Phys. 115, 123703 (2014).

  23. C. Jirauschek and T. Kubis, Modeling techniques for quantum cascade lasers, Appl. Phys. Rev. 1, 011307 (2014).

  24. J. E. Fonseca, T. Kubis, M. Povolotskyi, B. Novakovic, A. Ajoy, G. Hedge, H. Ilatikhameneh, Z. Jiang, P. Sengupta, Y. Tan, and G. Klimeck, Efficient and realistic device modeling from atomic detail to the nanoscale, J. Comput. Electron. 12, 592 (2013).

  25. S. R. Mehrotra, M. Povolotskyi, D. C. Elias, T. Kubis, J. J. M. Law, M. J. W. Rodwell and G. Klimeck, Simulation study of thin-body ballistic n-MOSFETs involving transport in mixed Γ-L valleys, IEEE Elect. Dev. Lett. 34, 1196 (2013).

  26. P. Sengupta, T. Kubis, Y. Tan, M. Povolotskyi, and G. Klimeck, Design principles for HgTe based Topological Insulator Devices, J. Appl. Phys. 114, 043702 (2013).

  27. S. R. Mehrotra, S.G. Kim, T. Kubis, M. Povolotskyi, M. S. Lundstrom, and G. Klimeck, Engineering Nanowire n-MOSFETs at Lg < 8 nm, IEEE Trans. Elect. Dev. 60, 2171 (2013).

  28. L. Zeng, Y. He, M. Povolotsky, X.Y. Liu, G. Klimeck, T. Kubis, Low Rank Approximation Method for Efficient Green's Function Calculation of Dissipative Quantum Transport, J. Appl. Phys. 113, 213707 (2013)

  29. Z. Jiang, M. A. Kuroda, Y. Tan, D. M. Newns, M. Povolotskyi, T. B. Boykin, T. Kubis, Gerhard Klimeck, and G. J. Martyna, Electron transport in nano-scaled piezoelectronic devices, Appl. Phys. Lett. 102, 193501 (2013).

  30. C. Deutsch, H. Detz, T. Zederbauer, A. M. Andrews, P. Klang, T. Kubis, G. Klimeck, M. E. Schuster, W. Schrenk, G. Strasser, K. Unterrainer, Probing scattering mechanisms with symmetric quantum cascade lasers, Optics Express 21, 7209 (2013).

  31. Y. Tan, M. Povolotskyi; T. Kubis, Y. He, Z. Jiang, G. Klimeck, T. Boykin, Empirical tight binding parameters for GaAs and MgO with explicit basis through DFT mapping, J. Comp. Electron. 12, 56 (2013).

  32. K. Fujita, M. Yamanishi, S. Furuta, K. Tanaka, T. Edamura, T. Kubis, and G. Klimeck, Indirectly pumped 3.7 THz InGaAs/InAlAs quantum-cascade lasers grown by metal-organic vapor-phase epitaxy, Optics Express 20, 20647 (2012).

  33. R. Kotlyar, T. Linton, R. Rios, M. Giles, S. Cea, K. Kuhn, M. Povolotskyi, T. Kubis, G. Klimeck, Does the low hole transport mass in <110> and <111> Si nanowires lead to mobility enhancements at high field and stress: a self-consistent tight-binding study, J. Appl. Phys. 111, 123718 (2012).

  34. H. Yasuda, T. Kubis, I. Hosako, and K. Hirakawa, Non-equilibrium Green's function calculation for GaN-based terahertz-quantum cascade laser structures, J. Appl. Phys. 111, 083105 (2012).

  35. T. Liu, T. Kubis, G. Klimeck, and Q. J. Wang, Design of three-well indirect pumping terahertz quantum cascade lasers for high optical gain based on nonequilibrium Green's function analysis, Appl. Phys. Lett. 100, 122110 (2012).

  36. S. Steiger, M. Povolotskyi, H.-H. Park, T. Kubis, and G. Klimeck, NEMO5: A Parallel Multiscale Nanoelectronics Modeling Tool, IEEE Transactions on Nanotechnology 10, 1464 (2011).

  37. S. Steiger, M. Salmani-Jelodar, D. Areshkin, A. Paul, T. Kubis, M. Povolotskyi, H.-H. Park, and G. Klimeck, Enhanced valence force field model for the lattice properties of gallium arsenide, Phys. Rev. B 84, 155204 (2011).

  38. T. Kubis, P. Vogl, Assessment of approximations in nonequilibrium Green’s function theory, Phys. Rev. B 83, 195304 (2011).

  39. T. Kubis, S. R. Mehrotra, and G. Klimeck, Design concepts of terahertz quantum cascade lasers: Proposal for terahertz laser efficiency improvements, Appl. Phys. Lett. 97, 261106 (2010).

  40. C. Deutsch, A. Benz, H. Detz, P. Klang, M. Nobile, A. M. Andrews, W. Schrenk, T. Kubis, P. Vogl, G. Strasser, and K. Unterrainer, Terahertz Quantum Cascade Lasers based on Type II InGaAs/GaAsSb/InP, Appl. Phys. Lett. 97, 261110 (2010).

  41. S. Agarwal, M. Povolotskyi, T. Kubis, and G. Klimeck, Adaptive quadrature for sharply spiked integrands, J. Comput. Electron. 9, 252 (2010).

  42. P. Vogl and T. Kubis, The non-equilibrium Green's function method: an introduction, Journal of Computational Electronics, J. Comput. Electron. 9, 237 (2010).

  43. A. Matyas, T. Kubis, P. Lugli, and C. Jirauschek, Comparison between semiclassical and full quantum transport analysis of THz quantum cascade lasers, Physica E 42, 2628 (2010).

  44. T. Kubis, C. Yeh, P. Vogl, A. Benz, G. Fasching, C. Deutsch, Theory of nonequilibrium quantum transport and energy dissipation in terahertz quantum cascade lasers, Phys. Rev. B 79, 195323 (2009).

  45. H. Yasuda, T. Kubis, P. Vogl, N. Sekine, I. Hosako, K. Hirakawa, Nonequilibrium Green's function calculation for four-level scheme terahertz quantum cascade lasers, Appl. Phys. Lett. 94, 151109 (2009).

  46. T. Kubis, P. Vogl, Predictive Quantum Theory of Current and Optical Gain in Quantum Cascade Lasers, Laser Physics 19, 762 (2009).

  47. T. Kubis, P. Vogl, Microscopic theory of spin-filtering in non-magnetic semiconductor nanostructures, phys. stat. sol. (c) 5, 290 (2008).

  48. T. Kubis, C. Yeh, P. Vogl, Non-equilibrium quantum transport theory: Current and gain in quantum cascade lasers, J. Comput. Electron. 7, 432 (2008).

  49. T. Kubis, C. Yeh, P. Vogl, Quantum theory of transport and optical gain in quantum cascade lasers, phys. stat. sol. (c) 5, 232 (2008).

  50. S. Birner, T. Kubis, P. Vogl, Simulation of quantum cascade lasers - optimizing laser performance, Photonik international 2, 60 (2008).

  51. S. Birner, T. Zibold, T. Andlauer, T. Kubis, M. Sabathil, A. Trellakis, P. Vogl, nextnano: General Purpose 3-D Simulations, IEEE Transactions on Electron Devices 54, 2137 (2007).

  52. T. Kubis, P. Vogl, Self-consistent quantum transport theory: Applications and assessment of approximate models, J. Comput. Electron. 6, 183 (2007).

  1. Nonequilibrium Green's Functions: Reliably Predicting Chemical Reactions

    07 Mar 2017 | Online Presentations | Contributor(s): Tillmann Christoph Kubis

    In this talk, an introductory overview of the nonequilibrium Green&rsquo;s function (NEGF) method will be given. NEGF results in state-of the art semiconductor nanodevices will illustrate the strengths of the method. Unique benefits of the method for molecular chemistry will be highlighted and pathways to extend the NEGF application space to fluids will be sketched.

  2. Transferable Tight Binding Model for Strained Heterostructures

    22 Oct 2016 | Online Presentations | Contributor(s): Yaohua TanMichael PovolotskyiTillmann Christoph KubisTimothy BoykinGerhard Klimeck

    IWCE 2015 presentation.

  3. NEMO5 and 2D Materials: Tuning Bandstructures, Wave Functions and Electrostatic Screening

    19 Oct 2016 | Online Presentations | Contributor(s): Tillmann Christoph Kubis

    In this talk, I will briefly discuss the MLWF approach and compare it to DFT and atomistic tight binding. Initial results using the MLWF approach for 2D material based devices will be discussed and compared to experiments. These results unveil systematic band structure changes as functions of the layer thickness and the applied gate potential. The electrostatic response depends on the location of the band edges in the Brillouin zone, their degeneracy and associated wavefunctions. All these properties turn out to be tunable. ...

  4. Self-energies: Opening Doors for Nanotechnology

    07 Apr 2016 | Online Presentations | Contributor(s): Tillmann Christoph Kubis

    In this talk, it will be shown how the concept of self-energies can be used to interface all these fields into the same nanotechnology modeling framework. Self-energies are most commonly used in the quantum transport method of nonequilibrium Green’s functions (NEGF). The NEGF method is widely accepted as the most consistent method for modeling coherent and incoherent effects....

  5. Mode Space Tight Binding Model for Ultra-Fast Simulations of III-V Nanowire MOSFETs and Heterojunction TFETs

    13 Nov 2015 | Online Presentations | Contributor(s): Aryan AfzalianJun HuangHesameddin IlatikhamenehSantiago Alonso Perez RubianoTillmann Christoph KubisMichael PovolotskyiGerhard Klimeck

    IWCE 2015 presentation.  we explore here the suitability of a mode space tight binding algorithm to various iii-v homo- and heterojunction nanowire devices. we show that in iii-v materials, the number of unphysical modes to eliminate is very high compared to the si case previously reported in the literature. nevertheless, we demonstrate here the possibility to clean iii-v mode space basis from the unphysical modes and achieve a significant speed up ratio (>: ; 150×: ; ), while...

  6. NEMO5: Why must we treat topological insulator nanowires atomically?

    15 Oct 2015 | Online Presentations | Contributor(s): Fan ChenMichael J. ManfraGerhard KlimeckTillmann Christoph Kubis

    IWCE 2015 presentation.  Abstract and more information to be added at a later date.

  7. Empirical Tight-binding Parameterization of SmSe in the sp3d5f7s* model

    26 Mar 2013 | Downloads | Contributor(s): Zhengping JiangMarcelo KurodaYaohua Tan, Dennis M. Newns, Michael PovolotskyiTimothy BoykinTillmann Christoph KubisGerhard Klimeck, Glenn J. Martyna

    The Empirical Tight Binding(ETB) method is widely used in atomistic device simulations. The reliability of such simulations depends very strongly on the choice of basis sets and the ETB parameters. The Piezoelectronic Transistor (PET) has been proposed as a post-CMOS device for fast, low-power switching. In this device the piezoresistive channel is metalized via the expansion of a relaxor piezoelectric element. The mixed-valence compound SmSe is a good choice of PET channel material …

  8. NEMO5 Latest Version Source

    19 Mar 2013 | Downloads | Contributor(s): James FonsecaMichael PovolotskyiTillmann Christoph KubisJean Michel D Sellier

    Revision 24185 uploaded on December 16th, 2016. Revision 23455 updated on August 8th, 2016   Revision 21229 updated on Sept 2, 2015.  Use this if you want to build NEMO5 from source. 

  9. Tight Binding Parameters by DFT mapping

    12 Sep 2012 | Presentation Materials | Contributor(s): Yaohua TanMichael PovolotskyiTillmann Christoph KubisYu HeZhengping JiangTimothy BoykinGerhard Klimeck

    The Empirical Tight Binding(ETB) method is widely used in atomistic device simulations. The reliability of such simulations depends very strongly on the choice of basis sets and the ETB parameters. The traditional way of obtaining the ETB parameters is by fitting to experiment data,or critical theoretical bandedges and symmetries rather than a foundational mapping. A further shortcoming of traditional ETB is the lack of an explicit basis. Alternatively, a DFT mapping process which constructs...

  10. NEMO5 Tutorials (2012 Summer School)

    19 Jul 2012 | Courses | Contributor(s): James FonsecaTillmann Christoph KubisMichael PovolotskyiJean Michel D SellierParijat SenguptaJunzhe GengMehdi Salmani JelodarSeung Hyun ParkGerhard Klimeck

    While the general topics presented in the summer school materials are still applicable, many details have changed.  If you are looking at these to learn how to use NEMO5, check out the newer materials here:    

  11. NEMO5 Tutorial 6A: Device Simulation - Transport (Double Gate)

    18 Jul 2012 | Online Presentations | Contributor(s): Mehdi Salmani JelodarSeung Hyun ParkZhengping JiangTillmann Christoph KubisMichael PovolotskyiGerhard Klimeck

  12. NEMO5 Overview Presentation PUBLISHED

    17 Jul 2012 | Online Presentations | Contributor(s): Tillmann Christoph KubisMichael PovolotskyiJean Michel D SellierJames FonsecaGerhard Klimeck

    This presentation gives an overview of the current functionality of NEMO5.

  13. Brillouin Zone Viewer

    25 Jan 2011 | Tools | Contributor(s): Prasad SarangapaniArun Goud AkkalaSebastian SteigerHong-Hyun ParkYosef BorgaTillmann Christoph KubisMichael PovolotskyiGerhard Klimeck

    Visualize Brillouin zones of different crystals and different unit cells

  14. Nonequilibrium Green’s functions theory: Transport and optical gain in THz quantum cascade lasers PUBLISHED

    26 Mar 2010 | Online Presentations | Contributor(s): Tillmann Christoph Kubis

    Quantum cascade lasers (QCLs) are promising sources of coherent THz radiation. However, state of the art THz-QCLs are still limited to cryogenic temperatures. The charge transport in these QCLs is subject to coherent quantum phenomena, such as quantum tunneling, confinement and interferences as well as significant incoherent scattering on phonons and device imperfections. Therefore, we require a predictive theory that treats coherent and incoherent transport on an equal footing. For this …

  15. Quantum transport in semiconductor nanostructures PUBLISHED

    04 Mar 2010 | Papers | Contributor(s): Tillmann Christoph Kubis

    PhD thesis of Tillmann Christoph Kubis The main objective of this thesis is to theoretically predict the stationary charge and spin transport in mesoscopic semiconductor quantum devices in the presence of phonons and device imperfections. It is well known that the nonequilibrium Green's function method (NEGF) is a very general and all-inclusive scheme for the description of exactly this kind of transport problem. Although the NEGF formalism has been derived in the 1960's, textbooks about …

  16. Resonant Tunneling Diode Simulation with NEGF

    18 Aug 2008 | Tools | Contributor(s): Hong-Hyun ParkZhengping JiangArun Goud AkkalaSebastian SteigerMichael PovolotskyiTillmann Christoph KubisJean Michel D SellierYaohua TanSungGeun KimMathieu LuisierSamarth AgarwalMichael McLennanGerhard KlimeckJunzhe Geng

    Simulate 1D RTDs using NEGF.

  17. 1D Heterostructure Tool

    04 Aug 2008 | Tools | Contributor(s): Arun Goud AkkalaSebastian SteigerJean Michel D SellierSunhee LeeMichael PovolotskyiTillmann Christoph KubisHong-Hyun ParkSamarth AgarwalGerhard KlimeckJames FonsecaArchana TankasalaKuang-Chung WangChin-Yi ChenFan Chen

    Poisson-Schrödinger Solver for 1D Heterostructures

  18. Band Structure Lab

    19 May 2006 | Tools | Contributor(s): Samik MukherjeeKai MiaoAbhijeet PaulNeophytos NeophytouRaseong KimJunzhe GengMichael PovolotskyiTillmann Christoph KubisArvind AjoyBozidar NovakovicJames FonsecaHesameddin IlatikhamenehSebastian SteigerMichael McLennanMark LundstromGerhard Klimeck

    Computes the electronic and phonon structure of various materials in the spatial configuration of bulk , quantum wells, and wires

  19. Quantum Dot Lab

    12 Nov 2005 | Tools | Contributor(s): Prasad SarangapaniJames FonsecaDaniel F MejiaJames CharlesWoody GilbertsonTarek Ahmed AmeenHesameddin IlatikhamenehAndrew RochéLars BjaalieSebastian SteigerDavid EbertMatteo ManninoHong-Hyun ParkTillmann Christoph KubisMichael PovolotskyiMichael McLennanGerhard Klimeck

    Compute the eigenstates of a particle in a box of various shapes including domes, pyramids and multilayer structures.

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© 2019 Tillmann Kubis