Spin-glass quantum phase transition in amorphous arrays of Rydberg atoms

TL;DR

This paper demonstrates through simulations that amorphous arrays of Rydberg atoms can host a quantum spin-glass phase, revealing a phase transition from paramagnetic to spin-glass states without long-range order.

Contribution

It introduces unbiased quantum Monte Carlo simulations of amorphous Rydberg atom arrays, showing evidence of a quantum spin-glass phase and highlighting the role of structural disorder.

Findings

Evidence of a quantum phase transition to a spin-glass phase.

Short-range isotropic antiferromagnetic correlations observed.

Distinct spin-overlap distribution with broad peaks and zero overlap weight.

Abstract

The experiments performed with neutral atoms trapped in optical tweezers and coherently coupled to the Rydberg state allow quantum simulations of paradigmatic Hamiltonians for quantum magnetism. Previous studies have focused mainly on periodic arrangements of the optical tweezers, which host various spatially ordered magnetic phases. Here, we perform unbiased quantum Monte Carlo simulations of the ground state of quantum Ising models for amorphous arrays of Rydberg atoms. These models are designed to feature well-controlled local structural properties in the absence of long-range order. Notably, by determining the Edwards-Anderson order parameter, we find evidence of a quantum phase transition from a paramagnetic to a spin-glass phase. The magnetic structure factor indicates short-range isotropic antiferromagnetic correlations. For the feasible sizes, the spin-overlap distribution features a nontrivial structure with two broad peaks and a sizable weight at zero overlap. The comparison against results for the clean kagome lattice, which features local structural properties similar to those of our amorphous arrays, highlights the important role of the absence of long-range structural order of the underlying array. Our findings indicate a route to experimentally implement the details of a Hamiltonian which hosts a quantum spin-glass phase.