Critical Petermann K Factor for Intensity Noise Squeezing

A. M. van Der Lee (1) , N. J. Van Druten (1) , M. P. Van Exter (1) , J. P. Woerdman (1) , Jean-Philippe Poizat (2) , Philippe Grangier (2)

1 Huygens Laboratory
2 Laboratoire Charles Fabry de l'Institut d'Optique / Optique quantique

We investigate the impact of the Petermann-excess-noise factor K≥1 on the possibility of intensity noise squeezing of laser light below the standard quantum limit. Using an N-mode model, we show that squeezing is limited to a floor level of 2(k-1) times the shot noise limit. Thus, even a modest Petermann factor significantly impedes squeezing, which becomes impossible when K ≥1.5. This appears as a serious limitation for obtaining sub-shot-noise light from practical semiconductor lasers. We present experimental evidence for our theory.

Domains: Quantum Physics [quant-ph]

A. M. van Der Lee, N. J. Van Druten, M. P. Van Exter, J. P. Woerdman, Jean-Philippe Poizat, et al.. Critical Petermann K Factor for Intensity Noise Squeezing. Physical Review Letters, 2000, 85 (22), pp.4711. ⟨hal-00554272⟩