Engineering a C-Phase quantum gate: optical design and experimental realization

TL;DR

This paper reports the design and experimental realization of a C-Phase quantum gate using the optical path degree of freedom of a single photon, demonstrating advanced interferometric techniques and multipartite entanglement characterization.

Contribution

It introduces a novel optical setup for implementing a C-Phase gate exploiting the photon’s path degree of freedom and extends the application of high stability interferometry.

Findings

Successful realization of a C-Phase quantum gate

Advanced interferometric setup demonstrated high stability

Multipartite entanglement of Phased Dicke states characterized

Abstract

A two qubit quantum gate, namely the C-Phase, has been realized by exploiting the longitudinal momentum (i.e. the optical path) degree of freedom of a single photon. The experimental setup used to engineer this quantum gate represents an advanced version of the high stability closed-loop interferometric setup adopted to generate and characterize 2-photon 4-qubit Phased Dicke states. Some experimental results, dealing with the characterization of multipartite entanglement of the Phased Dicke states are also discussed in detail.