Quantum-limited discrimination of laser light and thermal light
Abstract
Understanding the fundamental sensitivity limit of an optical sensor requires a full quantum mechanical description of the sensing task. In this work, we calculate the fundamental (quantum) limit for discriminating between pure laser light and thermal noise in a photon-starved regime. The Helstrom bound for discrimination error probability for single mode measurement is computed along with error probability bounds for direct detection, coherent homodyne detection and the Kennedy receiver. A generalized Kennedy (GK) receiver is shown to closely approach the Helstrom limit. We present an experimental demonstration of this sensing task and demonstrate dB improvement in discrimination sensitivity over direct detection using a GK receiver, and an improvement of in error probability over coherent detection.
Keywords
Cite
@article{arxiv.1912.06718,
title = {Quantum-limited discrimination of laser light and thermal light},
author = {Jonathan L. Habif and Arunkumar Jagannathan and Samuel Gartenstein and Phoebe Amory and Saikat Guha},
journal= {arXiv preprint arXiv:1912.06718},
year = {2021}
}
Comments
7 pages, 3 figures