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arXiv · 2107.11284

Determinantal Quantum Monte Carlo solver for Cluster Perturbation Theory

Edwin W. Huang·Yao Wang
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Abstract

Cluster Perturbation Theory (CPT) is a technique for computing the spectral function of fermionic models with local interactions. By combining the solution of the model on a finite cluster with perturbation theory on intra-cluster hoppings, CPT provides access to single-particle properties with arbitrary momentum resolution while incurring low computational cost. Here, we introduce Determinantal Quantum Monte Carlo (DQMC) as a solver for CPT. Compared to the standard solver, exact diagonalization (ED), the DQMC solver reduces finite size effects through utilizing larger clusters, allows study of temperature dependence, and enables large-scale simulations of a greater set of models. We discuss the implementation of the DQMC solver for CPT and benchmark the CPT+DQMC method for the attractive and repulsive Hubbard models, showcasing its advantages over standard DQMC and CPT+ED simulations.

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Edwin W. Huang, Yao Wang. 2021-07-23. Determinantal Quantum Monte Carlo solver for Cluster Perturbation Theory. https://arxiv.org/abs/2107.11284

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