M. Usman

Towards low-loss telecom-wavelength photonic devices by designing GaBixAs1-x/GaAs core-shell nanowires

Muhammad Usman

Journal article  |  2019  |  Nanoscale

Nanowires are versatile nanostructures, which allow an exquisite control over bandgap energies and charge carrier dynamics making ..

Atomistic tight binding study of quantum confined Stark effect in GaBixAs1-x/GaAs quantum wells

Muhammad Usman

Journal article  |  2019  |  Journal of Physics: Condensed Matter

Recently, there has been tremendous research interest in novel bismide semiconductor materials (such as GaBi x As1-x ) for wavelen..

Unusual bandgap bowing in highly mismatched ZnOS alloys: Atomistic tight-binding band anti-crossing model

Saad M Alqahtani, Muhammad Usman, Shaikh S Ahmed

Journal article  |  2019  |  Journal of Applied Physics

An atomistic band anticrossing (BAC) model is developed and used to study “unusual bowing” in energy bandgap and its dependence on..

Global, regional, and national burden of neurological disorders, 1990-2016: a systematic analysis for the Global Burden of Disease Study 2016

Valery L Feigin, Emma Nichols, Tahiya Alam, Marlena S Bannick, Ettore Beghi, Natacha Blake, William J Culpepper, E Ray Dorsey, Alexis Elbaz, Richard G Ellenbogen, James L Fisher, Christina Fitzmaurice, Giorgia Giussani, Linda Glennie, Spencer L James, Catherine Owens Johnson, Nicholas J Kassebaum, Giancarlo Logroscino, Benoit Marin, W Cliff Mountjoy-Venning, et al.

Journal article  |  2019  |  The Lancet Neurology

Atomic-level characterisation of quantum computer arrays by machine learning

Muhammad Usman, Yi Zheng Wong, Charles Hill, Lloyd Hollenberg

Journal article  |  2019  |  arXiv:1904.01756

Impact of Disorder on the Optoelectronic Properties of GaNyAs1-x-yBix Alloys and Heterostructures

Muhammad Usman, Christopher A Broderick, Eoin P O'Reilly

Journal article  |  2018  |  Physical Review Applied

Valley Filtering in Spatial Maps of Coupling between Silicon Donors and Quantum Dots

J Salfi, B Voisin, A Tankasala, J Bocquel, M Usman, MY Simmons, LCL Hollenberg, R Rahman, S Rogge

Journal article  |  2018  |  Physical Review X

Measurements and atomistic theory of electron g-factor anisotropy for phosphorus donors in strained silicon

M Usman, H Huebl, AR Stegner, CD Hill, MS Brandt, LCL Hollenberg

Journal article  |  2018  |  Physical review B: Condensed matter and materials physics

Two-electron states of a group-V donor in silicon from atomistic full configuration interactions

Archana Tankasala, Joseph Salfi, Juanita Bocquel, Benoit Voisin, Muhammad Usman, Gerhard Klimeck, Michelle Y Simmons, Lloyd CL Hollenberg, Sven Rogge, Rajib Rahman

Journal article  |  2018  |  Physical review B: Condensed matter and materials physics

Large-scale atomistic simulations demonstrate dominant alloy disorder effects in GaBi(x)As1-(x)/GaAs multiple quantum wells

Muhammad Usman

Journal article  |  2018  |  Physical Review Materials

Towards visualisation of central-cell-effects in scanning tunnelling microscope images of subsurface dopant qubits in silicon

Muhammad Usman, Benoit Voisin, Joe Salfi, Sven Rogge, Lloyd CL Hollenberg

Journal article  |  2017  |  Nanoscale

Spatial metrology of dopants in silicon with exact lattice site precision

M Usman, J Bocquel, J Salfi, B Voisin, A Tankasala, R Rahman, MY Simmons, S Rogge, LCL Hollenberg

Journal article  |  2016  |  Nature Nanotechnology

Strain and electric field control of hyperfine interactions for donor spin qubits in silicon

M Usman, CD Hill, R Rahman, G Klimeck, MY Simmons, S Rogge, LCL Hollenberg

Journal article  |  2015  |  Phys. Rev. B

Multimillion-atom modeling of InAs/GaAs quantum dots: interplay of geometry, quantization, atomicity, strain, and linear and quadratic polarization fields

Shaikh Ahmed, Sasi Sundaresan, Hoon Ryu, Muhammad Usman

Journal article  |  2015  |  Journal of Computational Electronics

Donor hyperfine Stark shift and the role of central-cell corrections in tight-binding theory

Muhammad Usman, Rajib Rahman, Joe Salfi, Juanita Bocquel, Benoit Voisin, Sven Rogge, Gerhard Klimeck, Lloyd LC Hollenberg

Journal article  |  2015  |  Journal of Physics: Condensed Matter

Multimillion Atom Simulation of Electronic and Optical Properties of Nanoscale Devices Using NEMO 3-D

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, Gerhard Klimeck

Book Chapter  |  2015

Understanding the electric field control of the electronic and optical properties of strongly-coupled multi-layered quantum dot molecules

Muhammad Usman

Journal article  |  2015  |  Nanoscale

Electrically injected GaAsBi quantum well lasers

SJ Sweeney, IP Marko, SR Jin, K Hild, Z Batool, P Ludewig, L Natterman, Z Bushell, W Stolz, K Volz, CA Broderick, M Usman, PE Harnedy, EP Oreilly, R Butkute, V Pacebutas, A Geiutis, A Krotkus

Conference Proceedings  |  2014  |  2014 International Semiconductor Laser Conference

Anisotropic electron g factor as a probe of the electronic structure of GaBixAs1-x/GaAs epilayers

Christopher A Broderick, Simone Mazzucato, Helene Carrere, Thierry Amand, Hejer Makhloufi, Alexandre Arnoult, Chantal Fontaine, Omer Donmez, Ayse Erol, Muhammad Usman, Eoin P O'Reilly, Xavier Marie

Journal article  |  2014  |  Physical Review B

Atomistic tight-binding study of electronic structure and interband optical transitions in GaBixAs1-x/GaAs quantum wells

Muhammad Usman, Eoin P O'Reilly

Journal article  |  2014  |  Applied Physics Letters

Electronic and optical properties of [110]-tilted InAs/GaAs quantum dot stacks

Muhammad Usman

Journal article  |  2014  |  Physical Review B

Tuning of polarization sensitivity in closely stacked trilayer InAs/GaAs quantum dots induced by overgrowth dynamics

Vittorianna Tasco, Muhammad Usman, Milena De Giorgi, Adriana Passaseo

Journal article  |  2014  |  Nanotechnology

Electrically injected GaAsBi Quantum Well Lasers

SJ Sweeney, IP Marko, SR Jin, K Hild, Z Batool, P Ludewig, L Natterman, Z Bushell, W Stolz, K Volz, CA Broderick, M Usman, PE Harnedy, EP O'Reilly, R Butkute, V Pacebutas, A Geizutis, A Krotkus

Conference Proceedings  |  2014  |  2014 24TH IEEE INTERNATIONAL SEMICONDUCTOR LASER CONFERENCE (ISLC 2014)

Size-dependent Electronic and Polarization Properties of Multi-Layer InAs Quantum Dot Molecules

M Usman

Book Chapter  |  2014

Derivation of 12-and 14-band k center dot p Hamiltonians for dilute bismide and bismide-nitride semiconductors

Christopher A Broderick, Muhammad Usman, Eoin P O'Reilly

Journal article  |  2013  |  Semiconductor Science and Technology

Analysis of the influence of the International Journal of Electrical Engineering Education on electrical engineering and electrical engineering education

Sadia Nawaz, Muhammad Usman, Johannes Strobel

Journal article  |  2013  |  International Journal of Electrical Engineering Education

12-band k . p model for dilute bismide alloys of (In)GaAs derived from supercell calculations

Christopher A Broderick, Muhammad Usman, Eoin P O'Reilly

Journal article  |  2013  |  Physica Status Solidi. B: Basic Research

Impact of alloy disorder on the band structure of compressively strained GaBixAs1-x

Muhammad Usman, Christopher A Broderick, Zahida Batool, Konstanze Hild, Thomas JC Hosea, Stephen J Sweeney, Eoin P O'Reilly

Journal article  |  2013  |  Physical Review B

Bismuth-Containing Compounds Preface

Handong Li, Zhiming M Wang

Book  |  2013  |  Springer Series in Materials Science

Understanding Polarization Properties of InAs Quantum Dots by Atomistic Modeling of Growth Dynamics

Vittorianna Tasco, Muhammad Usman, Maria Teresa Todaro, Milena De Giorgi, Adriana Passaseo

Conference Proceedings  |  2013  |  AIP Conference Proceedings

Theory of the Electronic Structure of Dilute Bismide Alloys: Tight-Binding and k . p Models

Christopher A Broderick, Muhammad Usman, Eoin P O'Reilly

Book Chapter  |  2013  |  Springer Series in Materials Science

Theory of the electronic structure of dilute bismide and bismide-nitride alloys of GaAs: Tight-binding and k.p models

Muhammad Usman, Christopher A Broderick, Eoin P O'Reilly

Conference Proceedings  |  2013  |  AIP Conference Proceedings

Theory of the electronic structure of dilute bismide and bismide-nitride alloys of GaAs: Tight-binding and kp models

M Usman, CA Broderick, E O'Reilly

Conference Proceedings  |  2013  |  AIP Conference Proceedings

Understanding Polarization Properties of InAs Quantum Dots by Atomistic Modeling of Growth Dynamics

V Tasco, M Usman, MT Todaro, M De Giorgi, A Passaseo

Conference Proceedings  |  2013  |  AIP Conference Proceedings

Atomistic theoretical study of electronic and polarization properties of single and vertically stacked elliptical InAs quantum dots

Muhammad Usman

Journal article  |  2012  |  Physical Review B

Band engineering in dilute nitride and bismide semiconductor lasers

CA Broderick, M Usman, SJ Sweeney, EP O'Reilly

Journal article  |  2012  |  Semiconductor Science and Technology

The polarization response in InAs quantum dots: theoretical correlation between composition and electronic properties

Muhammad Usman, Vittorianna Tasco, Maria Teresa Todaro, Milena De Giorgi, Eoin P O'Reilly, Gerhard Klimeck, Adriana Passaseo

Journal article  |  2012  |  Nanotechnology

Tight-binding analysis of the electronic structure of dilute bismide alloys of GaP and GaAs

Muhammad Usman, Christopher A Broderick, Andrew Lindsay, Eoin P O'Reilly

Journal article  |  2011  |  Physical Review B

In-plane polarization anisotropy of ground state optical intensity in InAs/GaAs quantum dots

Muhammad Usman

Journal article  |  2011  |  Journal of Applied Physics

Experimental and atomistic theoretical study of degree of polarization from multilayer InAs/GaAs quantum dot stacks

Muhammad Usman, Tomoya Inoue, Yukihiro Harda, Gerhard Klimeck, Takashi Kita

Journal article  |  2011  |  Physical Review B

Quantitative excited state spectroscopy of a single InGaAs quantum dot molecule through multi-million-atom electronic structure calculations

Muhammad Usman, Yui-Hong Matthias Tan, Hoon Ryu, Shaikh S Ahmed, Hubert J Krenner, Timothy B Boykin, Gerhard Klimeck

Journal article  |  2011  |  Nanotechnology

Experimental and theoretical study of polarization-dependent optical transitions in InAs quantum dots at telecommunication-wavelengths (1300-1500 nm)

Muhammad Usman, Susannah Heck, Edmund Clarke, Peter Spencer, Hoon Ryu, Ray Murray, Gerhard Klimeck

Journal article  |  2011  |  Journal of Applied Physics

Tight binding analysis of the electronic structure of dilute bismide and nitride alloys of GaAs

CA Broderick, M Usman, A Lindsay, EP O'Reilly

Conference Proceedings  |  2011  |  2011 13th International Conference on Transparent Optical Networks

Quantum confined stark shift and ground state optical transition rate in [100] laterally biased InAs/GaAs quantum dots

M Usman, H Ryu, S Lee, YH Tan, G Klimeck

Conference Proceedings  |  2009  |  2009 13th International Workshop on Computational Electronics IWCE 2009 Proceedings

Time-resolved luminescence studies of proton-implanted GaN

A Pinos, S Marcinkevicius, M Usman, A Hallen

Journal article  |  2009  |  Applied Physics Letters

Moving Toward Nano-TCAD Through Multimillion-Atom Quantum-Dot Simulations Matching Experimental Data

Muhammad Usman, Hoon Ryu, Insoo Woo, David S Ebert, Gerhard Klimeck

Journal article  |  2009  |  IEEE Transactions on Nanotechnology

NEMO 3-D and OMEN: Nanoelectronic modeling tools for advanced semiconductor device studies and their deployment on nanoHUB.org

Gerhard Klimeck, Mathieu Luisier, Rajib Rahman, Muhammad Usman, Neerav Kharche, Hoon Ryu, Sunhee Lee, Dragica Vasileska

Conference Proceedings  |  2009  |  ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY

Strain-engineered self-organized InAs/GaAs quantum dots for long wavelength (1.3 mu m-1.5 mu m) optical applications

Muhammad Usman, Dragica Vasileska, Gerhard Klimeck

Conference Proceedings  |  2009  |  AIP Conference Proceedings

Quantum Confined Stark Shift and Ground State Optical Transition Rate in [100] Laterally Biased InAs/GaAs Quantum Dots

Muhammad Usman, Hoon Ryu, Sunhee Lee, Yui H Tan, Gerhard Klimeck

Conference Proceedings  |  2009  |  IWCE-13: 2009 13TH INTERNATIONAL WORKSHOP ON COMPUTATIONAL ELECTRONICS

Multimillion Atom Simulations with Nemo3D

S Ahmed, M Usman, G Klimeck

Book Chapter  |  2009

Atomistic tight binding study of strain-reduced confinement potentials in identical and non-identical InAs/GaAs vertically stacked quantum dots

M Usman, S Ahmed, G Klimeck

Conference Proceedings  |  2008  |  2008 8th IEEE Conference on Nanotechnology

A Tight Binding Study of Strain-Reduced Confinement Potentials in Identical and Non-Identical InAs/GaAs Vertically Stacked Quantum Dots

M Usman, undefined Ahmed, undefined Klimeck

Conference Proceedings  |  2008  |  2008 8th IEEE Conference on Nanotechnology

Atomistic simulation of realistically sized nanodevices using NEMO 3-D - Part II: Applications

Gerhard Klimeck, Shaikh Shahid Ahmed, Neerav Kharche, Marek Korkusinski, Muhammad Usman, Marta Prada, Timothy B Boykin

Journal article  |  2007  |  IEEE Transactions on Electron Devices

Atomistic simulation of non-degeneracy and optical polarization anisotropy in pyramidal quantum dots

S Ahmed, M Usman, N Kharche, A Schliwa, G Klimeck

Conference Proceedings  |  2007  |  2nd IEEE International Conference on Nano/Micro Engineered and Molecular Systems, 2007

Strain and electronic structure interactions in realistically-scaled quantum dot stacks

Muhammad Usman, Shaikh Ahmed, Marek Korkusinski, Clemens Heitzinger, Gerhard Klimeck

Conference Proceedings  |  2007  |  AIP Conference Proceedings

Atomistic simulation of non-degeneracy and optical polarization anisotropy in pyramidal quantum dots

Shaikh Ahmed, Muhammad Usman, Neerav Kharche, Andrei Schliwa, Gerhard Klimeck

Conference Proceedings  |  2007  |  2007 2ND IEEE INTERNATIONAL CONFERENCE ON NANO/MICRO ENGINEERED AND MOLECULAR SYSTEMS, VOLS 1-3

Symmetry breaking and fine structure splitting in zincblende quantum dots: Atomistic simulations of long-range strain and piezoelectric field

Shaikh Ahmed, Muhammad Usman, Clemens Heitzinger, Rajib Rahman, Andrei Schliwa, Gerhard Klimeck

Conference Proceedings  |  2007  |  AIP Conference Proceedings