Quantum Algorithms for the computation of quantum thermal averages at work

TL;DR

This paper explores the practical implementation of quantum algorithms, specifically the Quantum-Quantum Metropolis algorithm, by simulating a small quantum spin system and comparing it with Quantum Metropolis Sampling.

Contribution

It provides an analysis of the Quantum-Quantum Metropolis algorithm's implementation and compares its performance with existing quantum sampling methods.

Findings

Quantum-Quantum Metropolis algorithm successfully simulates a three-spin system.

Comparison shows differences in systematic errors between algorithms.

Results inform future practical quantum thermal average computations.

Abstract

Recently, a variety of quantum algorithms have been devised to estimate thermal averages on a genuine quantum processor. In this paper, we consider the practical implementation of the so-called Quantum-Quantum Metropolis algorithm. As a testbed for this purpose, we simulate a basic system of three frustrated quantum spins and discuss its systematics, also in comparison with the Quantum Metropolis Sampling algorithm.