Publications (59)
Stochastic GW with the Orthogonalized Projector Augmented Wave Method
Dimitri Bazile, Minh Nguyen, Yuji Kon +2
We introduce stochastic GW with the orthogonalized projector augmented-wave method (OPAW-sGW). This implementation enables accurate quasiparticle band gaps on significantly coarser…
StochasticGW-GPU: rapid quasi-particle energies for molecules beyond 10000 atoms
Phillip S. Thomas, Minh Nguyen, Dimitri Bazile +6
is a code for computing accurate Quasi-Particle (QP) energies of molecules and material systems in the GW approximation. utilizes th…
Environment-Induced Exciton Renormalization in the Photosystem II Reaction Center
Tucker Allen, Barry Y. Li, Nadine C. Bradbury +1
Protein electrostatics tune excitation energies in the Photosystem II reaction center (PSII-RC), yet a fully quantum-mechanical many-body description of how the surrounding protein…
Stochastic density functional theory
Marcel David Fabian, Ben Shpiro, Eran Rabani +2
Linear-scaling implementations of density functional theory (DFT) reach their intended efficiency regime only when applied to systems having a physical size larger than the range o…
Expeditious stochastic approach for MP2 energies in large electronic systems
Daniel Neuhauser, Eran Rabani, Roi Baer
A fast stochastic method for calculating the 2nd order Møller-Plesset (MP2) correction to the correlation energy of large systems of electrons is presented. The approach is based…
Equilibrium configurations of large nanostructures using the embedded saturated-fragments stochastic density functional theory
Eitam Arnon, Eran Rabani, Daniel Neuhauser +1
An \emph{ab initio} Langevin dynamics approach is developed based on stochastic density functional theory (sDFT) within a new \emph{embedded saturated } \emph{fragment }formalism,…
Stochastic Density Functional Theory: Real- and Energy-Space Fragmentation for Noise Reduction
Ming Chen, Roi Baer, Daniel Neuhauser +1
Stochastic density functional theory (sDFT) is becoming a valuable tool for studying ground state properties of extended materials. The computational complexity of describing the K…
Stochastic Optimally-Tuned Ranged-Separated Hybrid Density Functional Theory
Daniel Neuhauser, Eran Rabani, Yael Cytter +1
We develop a stochastic formulation of the optimally-tuned range-separated hybrid density functional theory which enables significant reduction of the computational effort and scal…
Optimized Attenuated Interaction: Enabling Stochastic Bethe-Salpeter Spectra for Large Systems
Nadine C. Bradbury, Tucker Allen, Minh Nguyen +2
We develop an improved stochastic formalism for the Bethe-Salpeter equation, based on an exact separation of the effective-interaction to two parts, where the l…
Stochastic embedding DFT: theory and application to p-nitroaniline
Wenfei Li, Ming Chen, Eran Rabani +2
Over this past decade, we combined the idea of stochastic resolution of identity with a variety of electronic structure methods. In our stochastic Kohn-Sham DFT method, the density…
Stochastic self-consistent Green's function second-order perturbation theory (sGF2)
Daniel Neuhauser, Roi Baer, Dominika Zgid
The second-order Green's function method (GF2) was shown recently to be an accurate self-consistent approach for electronic structure of correlated systems since the self-energy ac…
Stochastic GW calculations for molecules
Vojtech Vlcek, Eran Rabani, Daniel Neuhauser +1
Quasiparticle (QP) excitations are extremely important for understanding and predicting charge transfer and transport in molecules, nanostructures and extended systems. Since densi…
Bogoliubov-like mode in the Tonks-Girardeau Gas
Igor V. Ovchinnikov, Daniel Neuhauser
We reformulate 1D boson-fermion duality in path-integral terms. The result is a 1D counterpart of the boson-fermion duality in the 2D Chern-Simons gauge theory. The theory is consi…
Stochastic Density Functional Theory at Finite Temperatures
Yael Cytter, Eran Rabani, Daniel Neuhauser +1
Simulations in the warm dense matter regime using finite temperature Kohn-Sham density functional theory (FT-KS-DFT), while frequently used, are computationally expensive due to th…
Real-Time Approach to the Dynamical Bethe-Salpeter Equation for Finite Systems
Tucker Allen, Barry Y. Li, Daniel Neuhauser
We present a real-time linear-response approach to solving the dynamical Bethe-Salpeter equation (BSE). The polarization part of the screened interaction is obtained from time-depe…
A guided stochastic energy-domain formulation of the second order Møller-Plesset perturbation theory
Qinghui Ge, Yi Gao, Roi Baer +2
We develop an alternative formulation in the energy-domain to calculate the second order Møller-Plesset (MP2) perturbation energies. The approach is based on repeatedly choosing f…
Bethe Salpeter Equation Spectra for Very Large Systems
Nadine Bradbury, Minh Nguyen, Justin R Caram +1
We present a highly efficient method for the extraction of optical properties of very large molecules via the Bethe-Salpeter equation. The crutch of this approach is the calculatio…
Real Space Orthogonal Projector-Augmented-Wave Method
Wenfei Li, Daniel Neuhauser
The projector augmented wave (PAW) method of Blöchl makes smooth but non-orthogonal orbitals. Here we show how to make PAW orthogonal, using a cheap transformation of the wave-fun…
Time-dependent Stochastic Bethe-Salpeter Approach
Eran Rabani, Roi Baer, Daniel Neuhauser
A time-dependent formulation for electron-hole excitations in extended finite systems, based on the Bethe-Salpeter equation (BSE), is developed using a stochastic wave function app…
A Stochastic Formulation of the Resolution of Identity: Application to Second Order Møller-Plesset Perturbation Theory
Tyler Y. Takeshita, Wibe A. de Jong, Daniel Neuhauser +2
A stochastic orbital approach to the resolution of identity (RI) approximation for 4-index 2-electron electron repulsion integrals (ERIs) is presented. The stochastic RI-ERIs are t…
Deterministic/Fragmented-Stochastic Exchange for Large Scale Hybrid DFT Calculations
Nadine C. Bradbury, Tucker Allen, Minh Nguyen +1
We develop an efficient approach to evaluate range-separated exact exchange for grid or plane-wave based representations within the Generalized Kohn-Sham DFT (GKS-DFT) framework. T…
Self-averaging stochastic Kohn-Sham density functional theory
Roi Baer, Daniel Neuhauser, Eran Rabani
We formulate the Kohn-Sham density functional theory (KS-DFT) as a statistical theory in which the electron density is deter-mined from an average of correlated stochastic densitie…
Efficient plane-wave approach to generalized Kohn-Sham density-functional theory of solids with mixed deterministic/stochastic exchange
Tucker Allen, Barry Y. Li, Tim Duong +2
An efficient mixed deterministic/sparse-stochastic plane-wave approach is developed for bandstructure calculations of large supercell periodic generalized-Kohn-Sham density functio…
Nonmonotonic band gap evolution in bent phosphorene nanosheets
Vojtech Vlcek, Eran Rabani, Roi Baer +1
Nonmonotonic bending-induced changes of fundamental band gaps and quasiparticle energies are observed for realistic nanoscale phosphorene nanosheets. Calculations using stochastic…
SOFI for Plasmonics: Extracting Near-field Intensity in the Far-Field at High Density
Robert C. Boutelle, Xiyu Yi, Daniel Neuhauser +1
Unlike normal fluorescent methods that use the intensity as a direct measurement of the localized enhanced field, we use blinking statistics of quantum dots (QDs). We have already…
Sparse-Stochastic Fragmented Exchange for Large-Scale Hybrid TDDFT Calculations
Mykola Sereda, Tucker Allen, Nadine C. Bradbury +2
We extend our recently developed sparse-stochastic fragmented exchange formalism for ground-state hybrid DFT (ngH-DFT) to calculate absorption spectra within linear-response time-d…
Stochastically Realized Observables for Excitonic Molecular Aggregates
Nadine C Bradbury, Chern Chuang, Arundhati P Deshmukh +4
We show that a stochastic approach enables calculations of the optical properties of large 2-dimensional and nanotubular excitonic molecular aggregates. Previous studies of such sy…
Stochastic self-consistent second-order Green's function method for correlation energies of large electronic systems
Daniel Neuhauser, Roi Baer, Dominika Zgid
The second-order Matsubara Green's function method (GF2) is a robust temperature dependent quantum chemistry approach, extending beyond the random-phase approximation. However, til…
Parameterized Attenuated Exchange for Generalized TDHF@ Applications
Barry Y. Li, Tim Duong, Tucker Allen +3
Building upon our previously developed time-dependent Hartree-Fock (TDHF)@ method, based on many-body perturbation theory and specifically the Bethe-Salpeter Equation (BSE), w…
Gapped-filtering for efficient Chebyshev expansion of the density projection operator
Minh Nguyen, Daniel Neuhauser
We develop the gapped-filtering method, whereby a short Chebyshev expansion accurately represents the density-matrix operator. The method optimizes the Chebyshev coefficients to gi…
Sublinear scaling for time-dependent stochastic density functional theory
Yi Gao, Daniel Neuhauser, Roi Baer +1
A stochastic approach to time-dependent density functional theory (TDDFT) is developed for computing the absorption cross section and the random phase approximation (RPA) correlati…
Simulating Exciton Transport with Complex Absorbing Potentials
Dimitri Bazile, Justin Caram, Chern Chuang +1
We introduce a stochastic framework based on complex absorbing potentials (CAPs) to investigate exciton transport in large molecular aggregates. Within this approach, CAPs act as n…
Tempering stochastic density functional theory
Minh Nguyen, Wenfei Li, Yangtao Li +3
We introduce a tempering approach with stochastic density functional theory (sDFT), labeled t-sDFT, which reduces the statistical errors in the estimates of observable expectation…
Quasiparticle spectra from molecules to bulk
Vojtech Vlcek, Eran Rabani, Daniel Neuhauser
A stochastic cumulant GW method is presented, allowing us to map the evolution of photoemission spectra, quasiparticle energies, lifetimes and emergence of collective excitations f…
Breaking the theoretical scaling limit for predicting quasi-particle energies: The stochastic GW approach
Daniel Neuhauser, Yi Gao, Christopher Arntsen +3
We develop a formalism to calculate the quasi-particle energy within the GW many-body perturbation correction to the density functional theory (DFT). The occupied and virtual orbit…
Dopant levels in large nanocrystals using stochastic optimally tuned range-separated hybrid density functional theory
Alex J. Lee, Ming Chen, Wenfei Li +3
We apply a stochastic version of an optimally tuned range-separated hybrid functional to provide insight on the electronic properties of P- and B- doped Si nanocrystals of experime…
Stochastic Resolution of Identity for Real-Time Second-Order Green's Function: Ionization Potential and Quasi-particle Spectrum
Wenjie Dou, Tyler Y. Takeshita, Ming Chen +3
We develop a stochastic resolution of identity approach to the real-time second-order Green's function (real-time sRI-GF2) theory, extending our recent work for imaginary-time Mats…
Transition to metallization in warm dense helium-hydrogen mixtures using stochastic density functional theory within the Kubo-Greenwood formalism
Yael Cytter, Eran Rabani, Daniel Neuhauser +3
The Kubo-Greenwood (KG) formula is often used in conjunction with Kohn-Sham (KS) density functional theory (DFT) to compute the optical conductivity, particularly for warm dense ma…
GW with hybrid functionals for large molecular systems
Tucker Allen, Minh Nguyen, Daniel Neuhauser
A low-cost approach for stochastically sampling static exchange during TDHF-type propagation is presented. This enables the use of an excellent hybrid DFT starting point for stocha…
Time-Dependent Density Functional Theory with the Orthogonal Projector Augmented Wave Method
Minh Nguyen, Tim Duong, Daniel Neuhauser
The projector augmented wave (PAW) method of Blöchl linearly maps smooth pseudo wavefunctions to the highly oscillatory all-electron DFT orbitals. Compared to norm-conserving pseu…
Efficient Langevin dynamics for "noisy" forces
Eitam Arnon, Eran Rabani, Daniel Neuhauser +1
Efficient Boltzmann-sampling using first-principles methods is challenging for extended systems due to the steep scaling of electronic structure methods with the system size. Stoch…
Stochastic Metholodgy Shows Molecular Interactions Protect 2D Polaritons
Nadine Bradbury, Raphael Ribeiro, Justin R. Caram +1
We introduce stochastic techniques that enable the simulations of polaritons resulting from placing giant 2D molecular aggregate crystals with interacting excitonic dyes in…
Mixed Planewave and Localized Orbital Basis for Sparse-Stochastic Hybrid TDDFT
Kyle Chen, Barry Y. Li, Tucker Allen +1
We present a mixed basis-set approach to obtain optical absorption spectra within a generalized Kohn-Sham time-dependent density functional theory framework. All occupied valence m…
Spontaneous charge carrier localization in extended one-dimensional systems
VojtÄch VlÄek, Helen R. Eisenberg, Gerd Steinle-Neumann +3
Charge carrier localization in extended atomic systems has been described previously as being driven by disorder, point defects or distortions of the ionic lattice. Here we show fo…
A Liouville equation for systems which exchange particles with reservoirs: transport through a nano-device
Igor V. Ovchinnikov, Daniel Neuhauser
A Redfield-like Liouville equation for an open system that couples to one or more leads and exchanges particles with them is derived. The equation is presented for a general case.…
First principles absorption spectra of Au nanoparticles: from quantum to classical
Samuel Hernandez, Yantao Xia, VojtÄch VlÄek +4
Absorption cross-section spectra for gold nanoparticles were calculated using fully quantum Stochastic Density Functional Theory and a classical Finite-Difference Time Domain (FDTD…
Embedded fragment stochastic density functional theory
Daniel Neuhauser, Roi Baer, Eran Rabani
We develop a method in which the electronic densities of small fragments determined by Kohn-Sham density functional theory (DFT) are embedded using stochastic DFT to form the exact…
Range-Separated Stochastic Resolution of Identity: Formulation and Application to Second Order Green's Function Theory
Wenjie Dou, Ming Chen, Tyler Y. Takeshita +3
We develop a range-separated stochastic resolution of identity approach for the -index electron repulsion integrals, where the larger terms (above a predefined threshold) are tr…
Simple eigenvalue-self-consistent
VojtÄch VlÄek, Roi Baer, Eran Rabani +1
We derive a general form of eigenvalue self-consistency for in the time domain and use it to obtain a simplified postprocessing eigenvalue self-consistency, which we label…
Probing the limits of optical cycling in a predissociative diatomic molecule
Qi Sun, Claire E. Dickerson, Jinyu Dai +6
Molecular predissociation is the spontaneous, nonradiative bond breaking process that can occur upon excitation. In the context of laser cooling, predissociation is an unwanted con…
Overlapped Embedded Fragment Stochastic Density Functional Theory for Covalently Bonded Materials
Ming Chen, Roi Baer, Daniel Neuhauser +1
The stochastic density functional theory (DFT) [Phys. Rev. Lett. 111, 106402 (2013)] is a valuable linear scaling approach to Kohn-Sham DFT that does not rely on the sparsity of th…
Tuning the range separation parameter in periodic systems
Wenfei Li, Vojtech Vlcek, Helen Eisenberg +3
Kohn-Sham DFT with optimally tuned range-separated hybrid (RSH) functionals provides accurate and nonempirical fundamental gaps for a wide variety of finite-size systems. The stand…
Swift beyond electrons using fractured stochastic orbitals
VojtÄch VlÄek, Wenfei Li, Roi Baer +2
We introduce the concept of fractured stochastic orbitals (FSOs), short vectors that sample a small number of space points and enable an efficient stochastic sampling of any genera…
Stochastic Time-Dependent DFT with Optimally Tuned Range-Separated Hybrids: Application to Excitonic Effects in Large Phosphorene Sheets
Vojtech Vlcek, Roi Baer, Daniel Neuhauser
We develop a stochastic approach to time-dependent DFT with optimally-tuned range-separated hybrids containing non-local exchange, for calculating optical spectra. The attractive e…
Hydrodynamic Tensor-DFT with correct susceptibility
Igor V. Ovchinnikov, Lizette A. Bartell, Daniel Neuhauser
In a previous work we developed a family of orbital-free tensor equations for DFT [J. Chem. Phys. 124, 024105 (2006)]. The theory is a combination of the coupled hydrodynamic momen…
No more gap-shifting: Stochastic many-body-theory based TDHF for accurate theory of polymethine cyanine dyes
Nadine C. Bradbury, Barry Y. Li, Tucker Allen +2
We introduce an individually fitted screened-exchange interaction for the time-dependent Hartree-Fock (TDHF) method and show that it resolves the missing binding energies in polyme…
Quantum-Spillover-Enhanced Surface-Plasmonic Absorption at the Interface of Silver and High-Index Dielectrics
Dafei Jin, Qing Hu, Daniel Neuhauser +6
We demonstrate an unexpectedly strong surface-plasmonic absorption at the interface of silver and high-index dielectrics based on electron and photon spectroscopy. The measured ban…
A density functional theory with correct long-range asymptotic behavior
Roi Baer, Daniel Neuhauser
We derive an exact representation of the exchange-correlation energy within density functional theory (DFT) which spawns a class of approximations leading to correct long-range asy…
Expeditious Stochastic Calculation of Random-Phase Approximation Energies for Thousands of Electrons in 3 Dimensions
Daniel Neuhauser, Eran Rabani, Roi Baer
A fast method is developed for calculating the Random-Phase-Approximation (RPA) correlation energy for density functional theory. The correlation energy is given by a trace over a…