All Dates/Times are Australian Eastern Standard Time (AEST)

# Technical Program

## Paper Detail

 Paper ID D3-S3-T4.1 Paper Title Fundamental Limits of Loss Sensing over Bosonic Channels Authors Zihao Gong, Christos N. Gagatsos, Saikat Guha, Boulat A. Bash, University of Arizona, United States Session D3-S3-T4: Quantum Detection & Estimation Chaired Session: Wednesday, 14 July, 22:40 - 23:00 Engagement Session: Wednesday, 14 July, 23:00 - 23:20 Abstract We consider the problem of estimating unknown loss $\eta$ over $n$ uses of single-mode lossy thermal noise bosonic channel under an average photon number constraint per mode. We prove that a product of $n$ two-mode squeezed vacuum (TMSV) states achieves minimal quantum Cramer-Rao bound (QCRB) over Gaussian quantum states in this scenario, and characterize the optimal receiver structure. We show that TMSV minimizes QCRB over all quantum states in the limit of low input photon number. Finally, we compare the performance of our optimal receiver for TMSV to other receivers.