title: Generation and application of twin beams from an optical parametric oscillator including an alpha-cut KTP crystal.
abstract: Measurement slight amounts of absorption of light with accuracy beyond the standard quantum limit has been experimentally demonstrated. The quantum-correlated twin beams used in the measurement were generated from a nondegenerate optical parametric oscillator including an alpha-cut KTiOPO(4) crystal pumped by an intracavity frequency-doubled Nd:YAG laser. The noise in the intensity difference between the twin beams was reduced by 88% below the standard quantum limit (SQL). The signal-to-noise ratio was improved by 7 dB with respect to the SQL of the total light employed in the experiment and by 4 dB with respect to that of the signal light.
authors: J
authors: J
authors: Gao
authors: F
authors: F
authors: Cui
authors: C
authors: C
authors: Xue
authors: C
authors: C
authors: Xie
authors: P
authors: P
authors: Kunchi