Passive, deterministic photonic CPHASE gate via two-level systems

TL;DR

This paper demonstrates that an array of identical two-level systems coupled to a one-dimensional waveguide can implement a high-fidelity conditional phase shift for quantum logic, with two proposed arrangements and analysis of physical realizations.

Contribution

It introduces two arrangements of emitters for implementing a photonic CPHASE gate and analyzes their physical realizations and limitations.

Findings

High fidelity conditional phase shift achievable

Two arrangements of emitters proposed

Analysis of physical limitations conducted

Abstract

We show that an array of identical two level systems coupled losslessly to a one dimensional waveguide is able to realize a high fidelity conditional phase shift useful for quantum logic. We propose two arrangements of emitters (one that relies on direct interactions between the emitters, and one that does not), and describe possible physical realizations and limitations.