65 citations · 113 across the 9 of their papers we have counts for
9 papers
Linear Ensemble-Constrained Quantum Monte Carlo: From Dilute Fermi Gas to Flat-Band Ferromagnetism
Tu Hong, Kun Chen, Xiao Yan Xu
We present a finite-temperature canonical-ensemble determinant quantum Monte Carlo algorithm that enforces an exact fermion number and enables numerically stable simulations of cor…
Superconductivity in Electron Liquids: Precision Many-Body Treatment of Coulomb Interaction
Xiansheng Cai, Tao Wang, Shuai Zhang +5
More than a century after discovery, the theory of conventional superconductivity remains incomplete. While the importance of electron-phonon coupling is understood, a controlled f…
A Novel Pseudo-Spectral Time-Domain Theory of Magnetic Neutron Scattering Illustrated Using A Uniformly Magnetized Sphere
Kun Chen
A universal numerical method is developed for the investigation of magnetic neutron scattering. By applying the pseudospectral-time-domain (PSTD) algorithm to the spinor version of…
Discrete Lehmann representation of three-point functions
Dominik Kiese, Hugo U. R. Strand, Kun Chen +3
We present a generalization of the discrete Lehmann representation (DLR) to three-point correlation and vertex functions in imaginary time and Matsubara frequency. The representati…
Partial Renormalization of Quasiparticle Interactions
Kun Chen
Nonlocal effective interactions are inherent to non-relativistic quantum many-body systems, but their systematic resummation poses a significant challenge known as the ``vertex pro…
A General PSTD Method to Solve Quantum Scattering in the Fresnel and Far-field regions by A Localized Potential of Arbitrary Form
Kun Chen
We present a time domain method to solve quantum scattering by an arbitrary potential of finite range. The scattering wave function in full space can be obtained, including the nea…
Low rank Green's function representations applied to dynamical mean-field theory
Nan Sheng, Alexander Hampel, Sophie Beck +4
Several recent works have introduced highly compact representations of single-particle Green's functions in the imaginary time and Matsubara frequency domains, as well as efficient…
libdlr: Efficient imaginary time calculations using the discrete Lehmann representation
Jason Kaye, Kun Chen, Hugo U. R. Strand
We introduce libdlr, a library implementing the recently introduced discrete Lehmann representation (DLR) of imaginary time Green's functions. The DLR basis consists of a collectio…
Discrete Lehmann representation of imaginary time Green's functions
Jason Kaye, Kun Chen, Olivier Parcollet
We present an efficient basis for imaginary time Green's functions based on a low rank decomposition of the spectral Lehmann representation. The basis functions are simply a set of…