Open AccessExperimental investigation of the intensity fluctuation joint probability and conditional distributions of the twin-beam quantum state
Author(s) -
Yun Zhang,
Katsuyuki Kasai,
Masayoshi Watanabe
Publication year - 2003
Publication title -
optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.11.000014
Subject(s) - optical parametric oscillator , physics , intensity (physics) , beam (structure) , optics , parametric statistics , statistical physics , quantum optics , spontaneous parametric down conversion , quantum mechanics , quantum , mathematics , statistics , laser , quantum entanglement
We give the intensity fluctuation joint probability of the twin-beam quantum state, which was generated with an optical parametric oscillator operating above threshold. Then we present what to our knowledge is the first measurement of the intensity fluctuation conditional probability distributions of twin beams. The measured inference variance of twin beams 0.62+/-0.02, which is less than the standard quantum limit of unity, indicates inference with a precision better than that of separable states. The measured photocurrent variance exhibits a quantum correlation of as much as -4.9+/-0.2 dB between the signal and the idler.