Minimally entangled typical thermal states algorithm with Trotter gates

TL;DR

This paper enhances the METTS algorithm's efficiency by integrating Trotter gates that preserve Abelian symmetries, significantly reducing autocorrelation and computation time in thermal state simulations.

Contribution

The authors introduce a Trotter gate operation into the METTS algorithm that maintains Abelian symmetries, improving sampling efficiency without breaking symmetry constraints.

Findings

Autocorrelation between states decreases by orders of magnitude.

Reduction in autocorrelation leads to faster computation times.

Effective for both canonical and grand canonical ensemble simulations.

Abstract

We improve the efficiency of the minimally entangled typical thermal states (METTS) algorithm without breaking the Abelian symmetries. By adding the operation of Trotter gates that respects the Abelian symmetries to the METTS algorithm, we find that a correlation between successive states in Markov-chain Monte Carlo sampling decreases by orders of magnitude. We measure the performance of the improved METTS algorithm through the simulations of the canonical ensemble of the Bose-Hubbard model and confirm that the reduction of the autocorrelation leads to the reduction of computation time. We show that our protocol using the operation of Trotter gates is effective also for the simulations of the grand canonical ensemble.