Microscopic Properties of Quantum Annealing -- Application to Fully Frustrated Ising Systems

TL;DR

This paper investigates the microscopic effects of quantum annealing on fully frustrated Ising spin systems, revealing how quantum fluctuations influence ground state selection and the limitations of quantum annealing in such degenerate systems.

Contribution

It provides a detailed analysis of quantum fluctuation effects in fully frustrated Ising systems, clarifying conditions under which quantum annealing effectively finds ground states.

Findings

Quantum annealing does not produce uniform probabilities for all ground states.

Quantum fluctuations induce an 'order by disorder' mechanism in frustrated systems.

The study clarifies microscopic properties affecting quantum annealing's success.

Abstract

In this paper we show quantum fluctuation effect of fully frustrated Ising spin systems. Quantum annealing has been expected to be an efficient method to find ground state of optimization problems. However it is not clear when to use the quantum annealing. In order to clarify when the quantum annealing works well, we have to study microscopic properties of quantum annealing. In fully frustrated Ising spin systems, there are macroscopically degenerated ground states. When we apply quantum annealing to fully frustrated systems, we cannot obtain each ground state with the same probability. This nature is consistent with "order by disorder" which is well-known mechanism in frustrated systems.