Linear optical quantum computation with imperfect entangled photon-pair sources and inefficient non-photon-number-resolving detectors

TL;DR

This paper presents a scheme for linear optical quantum computing that tolerates imperfect photon sources and detectors, achieving a loss threshold of over 50%, and remains robust against correlated losses.

Contribution

It introduces a loss-tolerant quantum computation scheme using imperfect sources and detectors, with a threshold unaffected by correlated losses, advancing practical quantum computing.

Findings

Efficiency threshold for loss tolerance > 1/2

Loss threshold unaffected by correlated loss

Scheme compatible with current experimental imperfections

Abstract

We propose a scheme for efficient cluster state quantum computation by using imperfect polarization-entangled photon-pair sources, linear optical elements and inefficient non-photon-number-resolving detectors. The efficiency threshold for loss tolerance in our scheme requires the product of source and detector efficiencies should be >1/2 - the best known figure. This figure applies to uncorrelated loss. We further find that the loss threshold is unaffected by correlated loss in the photon pair source. Our approach sheds new light on efficient linear optical quantum computation with imperfect experimental conditions.