Quantum Annealing in a Kinetically Constrained System

TL;DR

This paper investigates how quantum annealing can outperform classical annealing in kinetically constrained systems by leveraging quantum tunneling through narrow barriers, using semiclassical simulations.

Contribution

It introduces a semiclassical simulation approach to demonstrate quantum annealing's efficiency in kinetically constrained systems with narrow barriers.

Findings

Quantum annealing can be more efficient than classical annealing in certain constrained systems.

Quantum tunneling through narrow barriers enhances relaxation dynamics.

Semiclassical scattering simulations effectively model quantum annealing processes.

Abstract

Classical and quantum annealing is discussed for a kinetically constrained chain of $N$ non-interacting asymmetric double wells, represented by Ising spins in a longitudinal field $h$. It is shown that in certain cases, where the kinetic constraints may arise from infinitely high but vanishingly narrow barriers appearing in the relaxation path of the system, quantum annealing exploiting the quantum-mechanical penetration of sufficiently narrow barriers may be far more efficient than its thermal counterpart. We have used a semiclassical picture of scattering dynamics to do our simulation for the quantum system.