Observation of a Many-Body Dynamical Phase Transition with a 53-Qubit Quantum Simulator

TL;DR

This paper reports the observation of a many-body dynamical phase transition using a 53-qubit quantum simulator based on trapped ions, revealing complex non-equilibrium phenomena beyond classical statistical mechanics.

Contribution

It demonstrates the use of a large-scale quantum simulator to directly observe a non-equilibrium phase transition in a long-range interacting spin system.

Findings

Observation of a dynamical phase transition in a 53-qubit system

High-fidelity single-shot measurement of many-body correlations

Uncovering computationally intractable features of long-range interactions

Abstract

A quantum simulator is a restricted class of quantum computer that controls the interactions between quantum bits in a way that can be mapped to certain difficult quantum many-body problems. As more control is exerted over larger numbers of qubits, the simulator can tackle a wider range of problems, with the ultimate limit being a universal quantum computer that can solve general classes of hard problems. We use a quantum simulator composed of up to 53 qubits to study a non-equilibrium phase transition in the transverse field Ising model of magnetism, in a regime where conventional statistical mechanics does not apply. The qubits are represented by trapped ion spins that can be prepared in a variety of initial pure states. We apply a global long-range Ising interaction with controllable strength and range, and measure each individual qubit with near 99% efficiency. This allows the single-shot measurement of arbitrary many-body correlations for the direct probing of the dynamical phase transition and the uncovering of computationally intractable features that rely on the long-range interactions and high connectivity between the qubits.