Linear optics and photodetection achieve near-optimal unambiguous coherent state discrimination

ORAL

Abstract

Coherent states of the quantum electromagnetic field, the quantum description of ideal laser light, are prime candidates as information carriers for optical communications.

A large body of literature exists on their quantum-limited estimation and discrimination. However, very little is known about the practical realizations of receivers for unambiguous state discrimination (USD) of coherent states. Here we fill this gap and outline a theory of USD with receivers that are allowed to employ: passive multimode linear optics, phase-space displacements, auxiliary vacuum modes, and on-off photon detection. Our results indicate that, in some regimes, these currently-available optical components are typically sufficient to achieve near-optimal unambiguous discrimination of multiple, multimode coherent states.

*UK National Quantum Technologies Programme and the Quantum Technology Hub in Quantum Communications awarded under EPSRC Grant Number EP/T001011/1. NSF Center for Quantum Networks, awarded under Grant Number EEC-1941583.

Publication: arXiv:2109.00008: https://arxiv.org/abs/2109.00008

Presenters

  • Jasminder S Sidhu

    • University of Strathclyde

Authors

  • Jasminder S Sidhu

    • University of Strathclyde
  • Michael S Bullock

    • University of Arizona
  • Saikat Guha

    • The University of Arizona
    • University of Arizona
  • Cosmo Lupo

    • Politecnico di Bari