Linear-optical generation of eigenstates of the two-site XY model

TL;DR

This paper demonstrates the experimental generation of eigenstates of the XY spin model using linear optical quantum circuits, paving the way for simulating quantum spin dynamics with photonic systems.

Contribution

It introduces a linear optical implementation of the XY model eigenstates using a simple quantum circuit with CNOT gates and tunable parameters.

Findings

Successfully generated eigenstates of the XY Hamiltonian.

Demonstrated tunability of coupling and magnetic field parameters.

Potential for future studies of quenching dynamics with linear optics.

Abstract

Much of the anticipation accompanying the development of a quantum computer relates to its application to simulating dynamics of another quantum system of interest. Here we study the building blocks for simulating quantum spin systems with linear optics. We experimentally generate the eigenstates of the XY Hamiltonian under an external magnetic field. The implemented quantum circuit consists of two CNOT gates, which are realized experimentally by harnessing entanglement from a photon source and by applying a CPhase gate. We tune the ratio of coupling constants and magnetic field by changing local parameters. This implementation of the XY model using linear quantum optics might open the door to the future studies of quenching dynamics using linear optics.