Berry's phase on photonic quantum computers

TL;DR

This paper presents a photonic quantum computing algorithm to simulate and observe Berry's phase, demonstrating its experimental realization and robustness against certain errors using linear optical operations.

Contribution

It introduces a CVQC algorithm for Berry's phase simulation using passive linear optics, enabling experimental observation and error mitigation strategies.

Findings

Successful experimental observation of Berry's phase on photonic hardware.

Demonstration of error cancellation through symmetric Aharonov-Anandan cycles.

Framework generalizes to non-adiabatic evolution scenarios.

Abstract

We formulate a continuous-variable quantum computing (CVQC) algorithm to study Berry's phase on photonic quantum computers. We demonstrate that CVQC allows the simulation of charged particles with orbital angular momentum under the influence of an adiabatically changing $\vec{B}$ field. Although formulated entirely in the CVQC setting, our construction uses only passive linear-optical operations (beam splitters and phase shifts), which act identically in single-photon photonic architectures. This enables experimental realisation on the Quandella Ascella platform, where we observe the Berry's phase phenomenon with interferometric measurement. We also generalise the framework to more rapid non-adiabatic evolution. By concatenating Aharonov-Anandan cycles for opposing magnetic fields we demonstrate that one can engineer a circuit in which dynamical phases and leading non-geometric errors cancel by symmetry, leaving the intrinsically robust geometric phase contribution.