Hamiltonian Engineering of collective XYZ spin models in an optical cavity

TL;DR

This paper demonstrates a versatile quantum simulation platform that engineers all-to-all interactions among 700 rubidium atoms, enabling the realization of complex spin models like the XYZ and two-axis counter-twisting, with broad applications in quantum sensing.

Contribution

It introduces a method to engineer tunable cavity-mediated interactions for simulating arbitrary quadratic spin Hamiltonians with large atomic ensembles.

Findings

Realized all-to-all tunable Heisenberg XYZ model.

First implementation of the two-axis counter-twisting model at mean-field level.

Platform's potential for advanced quantum sensing applications.

Abstract

Quantum simulation using synthetic quantum systems offers unique opportunities to explore open questions in many-body physics and a path for the generation of useful entangled states. Nevertheless, so far many quantum simulators have been fundamentally limited in the models they can mimic. Here, we are able to realize an all-to-all interaction with arbitrary quadratic Hamiltonian or effectively an infinite range tunable Heisenberg XYZ model. This is accomplished by engineering cavity-mediated four-photon interactions between 700 rubidium atoms in which we harness a pair of momentum states as the effective pseudo spin or qubit degree of freedom. Using this capability we realize for the first time the so-called two-axis counter-twisting model at the mean-field level. The versatility of our platform to include more than two relevant momentum states, combined with the flexibility of the simulated Hamiltonians by adding cavity tones opens rich opportunities for quantum simulation and quantum sensing in matter-wave interferometers and other quantum sensors such as optical clocks and magnetometers