Mismatch in the Inverse-Squeezing Kennedy Receiver for Binary Displaced Squeezed-State Discrimination
Abstract
We analyze mismatch in the inverse-squeezing Kennedy receiver for binary displaced squeezed vacuum state discrimination. Mismatch is shown to be equivalent to a residual squeezing after nulling, which modifies the output photon-number statistics and makes the optimal maximum-a-posteriori (MAP) rule generally non-single-threshold. We find that the receiver is much more sensitive to phase mismatch than to amplitude mismatch. Under amplitude-only mismatch, the saturation error with finite-resolution photon-number-resolving detection exhibits a parity-step scaling, decreasing only when the detector resolution crosses even-photon thresholds. These results clarify the physical origin of mismatch-induced degradation and identify phase locking as the key requirement for practical implementations.
Keywords
Cite
@article{arxiv.2601.19093,
title = {Mismatch in the Inverse-Squeezing Kennedy Receiver for Binary Displaced Squeezed-State Discrimination},
author = {Enhao Bai and Tianyi Wu and Huankai Zhang and Jian Peng and Chen Dong and Fengkai Sun and Laiyuan Tong and Zhenrong Zhang and Chun Zhou and Yaping Li},
journal= {arXiv preprint arXiv:2601.19093},
year = {2026}
}