Harmonically trapped fermions in two dimensions: ground-state energy and contact of SU(2) and SU(4) systems via nonuniform lattice Monte Carlo

TL;DR

This paper investigates the ground-state energy and contact properties of harmonically trapped, unpolarized fermion systems with SU(2) and SU(4) symmetries in two dimensions using a novel nonuniform lattice Monte Carlo method, revealing the dominance of Nf-body physics at strong coupling.

Contribution

It introduces a nonuniform lattice Monte Carlo approach to study 2D fermion systems with multiple spin degeneracies, providing new insights into their ground-state properties.

Findings

Ground-state energy and contact vary with coupling strength.

Nf-body physics dominates at strong coupling.

Method effectively captures two-body binding energy effects.

Abstract

We study harmonically trapped, unpolarized fermion systems with attractive interactions in two spatial dimensions with spin degeneracies Nf = 2 and 4 and N/Nf = 1, 3, 5, and 7 particles per flavor. We carry out our calculations using our recently proposed quantum Monte Carlo method on a nonuniform lattice. We report on the ground-state energy and contact for a range of couplings, as determined by the binding energy of the two-body system, and show explicitly how the physics of the Nf-body sector dominates as the coupling is increased.