Low-noise photorefractive amplification and detection of very weak signal beams.
We present theoretical and experimental analyses of the signal-to-noise ratio (SNR) of photorefractive two-wave mixing detection that uses BaTiO(3). The influence of beam fanning is taken into account in the detection process. Different known methods to enhance the SNR of the detection are theoretically and experimentally compared. A 10-fold improvement of the SNR is obtained, and the detection of a 1-pW signal intensity for a SNR of 50 is achieved for two of them.
S
S
Breugnot
H
H
Rajbenbach
M
M
Defour
J P
JP
Huignard