The Influence of Experimental Imperfections on Photonic GHZ State Generation

TL;DR

This paper investigates how practical imperfections like loss and distinguishability affect the generation of photonic GHZ states, identifying dominant factors and feasible regimes for quantum computing implementation.

Contribution

It provides a detailed simulation-based analysis of imperfections in photonic GHZ state generation, highlighting the dominant sources for different photon sources and realistic parameter regimes.

Findings

Photon loss and distinguishability significantly impact fidelity and success probability.

Different imperfections dominate depending on the photon source type.

Certain parameter regimes are identified as promising for near-future photonic quantum computing.

Abstract

While the advantages of photonic quantum computing, including direct compatibility with communication, are apparent, several imperfections such as loss and distinguishability presently limit actual implementations. These imperfections are unlikely to be completely eliminated, and it is therefore beneficial to investigate which of these are the most dominant and what is achievable under their presence. In this work, we provide an in-depth investigation of the influence of photon loss, multi-photon terms and photon distinguishability on the generation of photonic 3-partite GHZ states via established fusion protocols. We simulate the generation process for SPDC and solid-state-based single-photon sources using realistic parameters and show that different types of imperfections are dominant with respect to the fidelity and generation success probability. Our results indicate what are the dominant imperfections for the different photon sources and in which parameter regimes we can hope to implement photonic quantum computing in the near future.