Polarimetric measurements of single-photon geometric phases

TL;DR

This paper presents a polarimetric setup using wave plates to measure geometric phases of single photons, demonstrating robustness against noise and enabling precise tests of geometric phase properties.

Contribution

It introduces a versatile polarimetric array capable of generating any SU(2) transformation and isolating geometric phases by nullifying dynamical contributions.

Findings

Successfully measured geometric phases with single photons.

Demonstrated insensitivity of the setup to various noise sources.

Showcased the array's capability to test geometric phase robustness.

Abstract

We report polarimetric measurements of geometric phases that are generated by evolving polarized photons along non-geodesic trajectories on the Poincar\'e sphere. The core of our polarimetric array consists of seven wave plates that are traversed by a single photon beam. With this array any SU(2) transformation can be realized. By exploiting the gauge invariance of geometric phases under U(1) local transformations, we nullify the dynamical contribution to the total phase, thereby making the latter coincide with the geometric phase. We demonstrate our arrangement to be insensitive to various sources of noise entering it. This makes the single-beam, polarimetric array a promising, versatile tool for testing robustness of geometric phases against noise.