iNLO — First-Principles Electronic Structure Code for Nonlinear Optical Properties

Features		Stand-alone NLO code interfaced with VASP & Quantum-ESPRESSO Highly parallelized and benchmarked on 10s to 1000s cores Support second harmonic generation and nonlinear photocurrent Support tensor symmetrization Support SHG calculations with and without spin-orbit coupling Under extensive development for efficient & accurate NLO calculations
Publications		Hua Wang and Xiaofeng Qian, Giant Optical Second Harmonic Generation in Two-Dimensional Multiferroics. Nano Letters 17, 5027-5034 (2017). Hua Wang and Xiaofeng Qian. Ferroicity-driven nonlinear photocurrent switching in time-reversal invariant ferroic materials. Science Advances 5, eaav9743 (2019). Hua Wang and Xiaofeng Qian. Ferroelectric nonlinear anomalous Hall effect in few-layer WTe2. npj Computational Materials 5, 119 (2019). Jun Xiao, Ying Wang, Hua Wang, C. D. Pemmaraju, Siqi Wang, Philipp Muscher, Edbert J. Sie, Clara M. Nyby, Thomas P. Devereaux, Xiaofeng Qian, Xiang Zhang, and Aaron M. Lindenberg. Berry curvature memory through electrically driven stacking transitions. Nature Physics 16, 1028-1034 (2020). Mohammad Taghinejad, Zihao Xu, Hua Wang, Hossein Taghinejad, Kyu-Tae Lee, Sean P. Rodrigues, Ali Adibi, Xiaofeng Qian, Tianquan Lian, and Wenshan Cai. Photocarrier-Induced Active Control of Second-Order Optical Nonlinearity in Monolayer MoS2. Small 16, 1906347 (2020). Jia Liang, Qiyi Fang, Hua Wang, Rui Xu, Shuai Jia, Yuxuan Guan, Qing Ai, Guanhui Gao, Hua Guo, Kaijun Shen, Xiewen Wen, Tanguy Terlier, Gary P. Wiederrecht, Xiaofeng Qian, Hanyu Zhu, and Jun Lou. Perovskite‐Derivative Valleytronics. Advanced Materials 32, 2004111 (2020). Hua Wang and Xiaofeng Qian. Electrically and magnetically switchable nonlinear photocurrent in РТ-symmetric magnetic topological quantum materials. npj Computational Materials 6, 199 (2020)

iNano — Materials Research and Education Platform

Features

Visualize crystal structures (CIF, XYZ, VASP, Quantum-ESPRESSO, Siesta) Visualize 2D/3D charge density, wavefunctions, eigenchannels & vector fields. Create and modify crystal and molecular structures Prepare input files with a single line for VASP, Quantum-ESPRESSO, Siesta. Analyze crystal and molecular structures Analyze computational results (DOS, PDOS, bonding, wavefunctions) Perform fast first-principles tight-binding electronic structure calculations User-extended functionality with additional modules and functions

QO — First-Principles Quasiatomic Orbitals for Ab Initio Tight-Binding Analysis

Features		Highly localized QOs by Bloch subspace optimization Exactly reproduce low-energy first-principles electronic structure Efficient calculations of 3D Fermi surface, DOS, PDOS Mulliken charge and bond order analysis for solids/surfaces/molecules Support NCPP, USPP and PAW Support point group symmetry for Bloch wave functions Support spin-unpolarized, spin-polarized, and spin-orbit coupling Generate real-space representation of localized QOs Generate tight-binding Hamiltonian in the QO basis Generate XCrySDen XSF/BXSF files for structures, QOs, and Fermi surfaces Interface with various DFT packages
Download		QO for Quantum-ESPRESSO 4.x
Publications		Xiaofeng Qian, Ju Li, Liang Qi, Cai-Zhuang Wang, Tzu-Liang Chan, Yong-Xin Yao, Kai-Ming Ho, and Sidney Yip. Quasiatomic orbitals for ab initio tight-binding analysis. Physical Review B 78, 245112 (2008). Tzu-Liang Chan, Yong-Xin Yao, Cai-Zhuang Wang, Wen-Cai Lu, Ju Li, Xiaofeng Qian, Sidney Yip, and Kai-Ming Ho. Highly localized quasiatomic minimal basis orbitals for mo from ab initio calculations. Phys. Rev. B 76, 205119 (2007)

QOT — Quantum Transport in Molecular and Nanoscale Electronics

Features		Interfaces to plane-wave DFT codes: including VASP, Dacapo, and PWscf (PW in Quantum-Espresso package) using norm conserving and ultrasoft pseudopotentials and PAW method QO module: construct highly localized QOs to reproduce electronic structure obtained from high-quality DFT planewave calculations up to a few eVs above the Fermi level; provide real-space QOs and their tight-binding Hamiltonian and overlap matrices, Mulliken and Lowdin charge analysis, (QO-projected) band structure and density of states, (energy/velocity/mass-resolved) Fermi surface for both spin-collinear and spin-noncollinear systems (with and without spin-orbit coupling) NEGF module: calculate phase-coherent quantum transport using non-equilibrium Green's function method in the QO basis-set together with density of states and conductance eigenchannel analysis GW/TDDFT module: calculate quasiparticle electronic structure and optical excitations using many-body perturbation theory in Hedin's GW approximation and time-dependent density-functional theory (TDDFT) in the QO basis-set (in development) Visualization module: visualize volumetric data including QOs, conductance eigenchannels, and Fermi surface using VTK and POV-Ray, and atomistic structure using AtomEye and XCrySDen Data flow: in the convenient NetCDF/HDF5 format
Publications		Xiaofeng Qian, Ju Li, and Sidney Yip. Calculating phase-coherent quantum transport in nanoelectronics with ab initio quasiatomic orbital basis set. Physical Review B 82, 195442 (2010).

RT-TDDFT — Real-Time Time-Dependent Density Functional Theory

Features		Support Vanderbilt ultrasoft pseudopotentials Optical absorption spectrum from real-time propagation method Real-time dynamics of electron transport through nanoscale junctions
Download		RT-TDDFT for Quantum ESPRESSO   (Implemented by Xiaofeng Qian and Davide Ceresoli)
Publications		Xiaofeng Qian, Ju Li, Xi Lin, and Sidney Yip. Time-dependent density functional theory with ultrasoft pseudopotentials: Real-time electron propagation across a molecular junction. Physical Review B 73, 035408 (2006).

GWW — Many-Body Perturbation Theory with GW+Wannier Approach

Features		Project lead by Professor Paolo Umari at University of Padova, Italy, et al. Calculate quasiparticle energies at the GW level Provide efficient representation of polarizability through Wannier function construction and product reduction Suitable for large molecular and solid-state systems
Download		GWW for Quantum ESPRESSO
Publications		Paolo Umari, Geoffrey Stenuit, and Stefano Baroni. Optimal representation of the polarization propagator for large-scale GW calculations. Physical Review B 79, 201104(R) (2009). Paolo Umari, Geoffrey Stenuit, and Stefano Baroni. GW quasiparticle spectra from occupied states only. Physical Review B 85, 115104 (2010). Paolo Umari, Xiaofeng Qian, Nicola Marzari, Geoffrey Stenuit, Luigi Giacomazzi, and Stefano Baroni. Accelerating GW calculations with optimal polarizability basis. Physica Status Solidi B 248, 527-536 (2011). Xiaofeng Qian, Paolo Umari, and Nicola Marzari. Photoelectron properties of DNA and RNA bases from many-body perturbation theory. Physical Review B 84, 075103 (2011). Xiaofeng Qian, Paolo Umari, and Nicola Marzari. First-principles investigation of organic photovoltaic materials C60, C70, [C60]PCBM, and bis-[C60]PCBM using a many-body G0W0-Lanczos approach. Physical Review B 91, 245105 (2015).