2012/03/31 by Rémi Blandino, Marco G. Genoni, Jean Etesse +4
Computer Science · Mathematics · Physics and Astronomy · #Direct-conversion receiver #Gaussian #Homodyne detection #Limit (mathematics) #Mathematical analysis #Mathematics #Physics #Quantum #Quantum Computing Algorithms and Architecture #Quantum Information and Cryptography #Quantum Mechanics and Applications #Quantum discord #Quantum entanglement #Quantum limit #Quantum mechanics #Statistical physics #quant-ph
paper · pdf · doi:10.1103/physrevlett.109.180402
published as Physical Review Letters 109, 18 (2012) 180402 · 5+3 pages, 3 figures, published version
arxiv created 2012/11/02 · openalex publication_date 2012/11/02 · arxiv updated 2013/02/22 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
We address the experimental estimation of Gaussian quantum discord for a two-mode squeezed thermal state, and demonstrate a measurement scheme based on a pair of homodyne detectors assisted by Bayesian analysis, which provides nearly optimal estimation for small value of discord. In addition, though homodyne detection is not optimal for Gaussian discord, the noise ratio to the ultimate quantum limit, as dictated by the quantum Cramer-Rao bound, is limited to about 10 dB.