17 citations · 46 across the 13 of their papers we have counts for
13 papers
Size Extensive Auxiliary-Field Quantum Monte Carlo with Perturbative Coupled Cluster Trial Wavefunction
Yichi Zhang, Ankit Mahajan, Yann Damour +1
In this work, we develop a size extensive Auxiliary-Field Quantum Monte Carlo (AFQMC) approach that scales as for local energy evaluation by treating the Coupled Cluster S…
Study of the triangular-lattice Hubbard model with constrained-path quantum Monte Carlo
Shu Fay Ung, Ankit Mahajan, David R. Reichman
We benchmark constrained-path Monte Carlo (CPMC) on the triangular-lattice Hubbard model for several fillings and values and show that symmetry-adapted trial wave functions sub…
Nuclear gradients from auxiliary-field quantum Monte Carlo and their application in geometry optimization and transition state search
Jo S. Kurian, Ankit Mahajan, Sandeep Sharma
In this article, we present a method for computing accurate and scalable nuclear forces within the phaseless auxiliary-field quantum Monte Carlo (AFQMC) framework. Our approach lev…
Evaluating Multiconfigurational Trials for Accurate Phaseless Auxiliary-Field Quantum Monte Carlo on 3d Transition Metal Complexes
Hung T. Vuong, Ankit Mahajan, John L. Weber +3
In this study, we evaluate multi-configurational trial wave function protocols for phaseless auxiliary field quantum Monte Carlo (ph-AFQMC) on transition metal containing systems.…
Excited states in auxiliary field quantum Monte Carlo
Ankit Mahajan, Sandeep Sharma, Shiwei Zhang +1
We systematically investigate the calculation of excited states in quantum chemistry using auxiliary field quantum Monte Carlo (AFQMC). Symmetry allows targeting of the lowest trip…
Mixed Quantum-Classical Methods for Polaron Spectral Functions
Haimi Nguyen, Arkajit Mandal, Ankit Mahajan +1
In this work, using two distinct semiclassical approaches, namely the mean-field Ehrenfest (MFE) method and the mapping approach to surface hopping (MASH), we investigate the spect…
Beyond CCSD(T) accuracy at lower scaling with auxiliary field quantum Monte Carlo
Ankit Mahajan, James H. Thorpe, Jo S. Kurian +3
We introduce a black-box auxiliary field quantum Monte Carlo (AFQMC) approach to perform highly accurate electronic structure calculations using configuration interaction singles a…
Improved modularity and new features in ipie: Toward even larger AFQMC calculations on CPUs and GPUs at zero and finite temperatures
Tong Jiang, Moritz K. A. Baumgarten, Pierre-François Loos +6
ipie is a Python-based auxiliary-field quantum Monte Carlo (AFQMC) package that has undergone substantial improvements since its initial release [J. Chem. Theory Comput., 2023, 19(…
Benchmarking the Exponential Ansatz for the Holstein model
Junjie Yang, Zhi-Hao Cui, Ankit Mahajan +3
Polarons are quasiparticles formed as a result of lattice distortions induced by charge carriers. The single-electron Holstein model captures the fundamentals of single polaron phy…
Ab Initio Polaron Wave Functions
Paul J. Robinson, Joonho Lee, Ankit Mahajan +1
In this work we demonstrate that accurate ground state wave functions may be constructed for polarons in a fully ab initio setting across the wide range of couplings associated wit…
Structure and dynamics of electron-phonon coupled systems using neural quantum states
Ankit Mahajan, Paul J. Robinson, Joonho Lee +1
In this work, we use neural quantum states (NQS) to describe the high-dimensional wave functions of electron-phonon coupled systems. We demonstrate that NQS can accurately and syst…
Unbiasing Fermionic Auxiliary-Field Quantum Monte Carlo with Matrix Product State Trial Wavefunctions
Tong Jiang, Bryan O'Gorman, Ankit Mahajan +1
In this work, we report, for the first time, an implementation of fermionic auxiliary-field quantum Monte Carlo (AFQMC) using matrix product state (MPS) trial wavefunctions, dubbed…
Scalable Ab Initio Electronic Structure Methods with Near Chemical Accuracy for Main Group Chemistry
Yujing Wei, Sibali Debnath, John L. Weber +3
This study evaluates the precision of widely recognized quantum chemical methodologies, CCSD(T), DLPNO-CCSD(T) and localized ph-AFQMC, for determining the thermochemistry of main g…