Density profiles and correlations of harmonically trapped ultracold fermions via complex Langevin

2022/12/21 by Felipe Attanasio, M. L. Bauer, Attanasio, Felipe +3
Physics and Astronomy · #Atomic and Subatomic Physics Research #Cold Atom Physics and Bose-Einstein Condensates #FOS: Physical sciences #High Energy Physics - Lattice (hep-lat) #Quantum Gases (cond-mat.quant-gas) #Strongly Correlated Electrons (cond-mat.str-el) #Theoretical and Computational Physics

paper · pdf · doi:10.48550/arxiv.2212.11314

openalex publication_date 2022/12/21 · openalex created_date 2023/01/04 · openalex updated_date 2026/07/28

Abstract

Standard lattice formulations of non-relativistic Fermi gases with two spin components suffer from a sign problem in the cases of repulsive contact interactions and attractive contact interactions with spin imbalance. We discuss the nature of this sign problem and the applicability of stochastic quantisation with complex Langevin evolution in both cases. For repulsive interactions, we find that the results converge, using adaptive step size scaling and a Gaussian regulator to modify the lattice action. We present results on density profiles and correlations of a harmonically trapped system in one spatial dimension.

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