Quantum Technologies That Reject Thermal Noise for Improved SNR in Coherent-State Ranging and Related Applications
Abstract
We investigate a few techniques to improve the signal-to-noise-ratio (SNR) of range finding, sensing, and other light-detection applications. First technique filters out low photon numbers using photon-number-resolving detectors (PNRDs). This technique has no classical analog and cannot be done with classical detectors. Then, we use quantum hypothesis testing a tool of quantum information theory to show this detection is optimal, for an unknown coherent-state return signal. It is done by deriving the limits of symmetric and asymmetric error probabilities and showing that this detection saturates those quantum limits. Finally, we show that a coherent state is the optimal probe in the sense that adding squeezing, single-mode and two-mode, does not improve the performance. In particular, quantum illumination does not outperform laser range finding when the phase is unusable. In addition, we checked other techniques; correlation functions and machine learning. Using first-order correlation function, a factor of 2 improvement is obtained, which by repeating N times can be 2N. Unfortunately, Higher order correlation functions don't present any improvement. Moreover, a machine learning code is used, but could not provide the same performance of optimal detection.
Document Details
- Document Type
- Technical Report
- Publication Date
- Aug 29, 2022
- Accession Number
- AD1180634
Entities
People
- Jonathan Dowling
Organizations
- Louisiana State University System