Quantum noise reduction in optical amplification
Abstract
Quantum fluctuations in optical amplification are investigated with a nondegenerate optical parametric amplifier whose internal idler mode is coupled to a squeezed vacuum. Reductions of the inherent quantum noise of the amplifier are observed with a minimum noise level 0.7 dB below the usual noise level of the amplifier with its internal idler mode in a vacuum state. With a small coherent field as the signal input, the amplified output exhibits an improvement in signal-to-noise ratio of 0.5 dB for the case of a squeezed-vacuum as compared to a vacuum state for the amplifier's internal mode.
- Publication:
-
Physical Review Letters
- Pub Date:
- May 1993
- DOI:
- Bibcode:
- 1993PhRvL..70.3239O
- Keywords:
-
- 42.50.Lc;
- 42.50.Dv;
- Quantum fluctuations quantum noise and quantum jumps;
- Nonclassical states of the electromagnetic field including entangled photon states;
- quantum state engineering and measurements