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Coexistence of thermal noise and squeezing in the intensity fluctuations of small laser diodes

Holger F. Hofmann·Ortwin Hess
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Abstract

The intensity fluctuations of laser light are derived from photon number rate equations. In the limit of short times, the photon statistics for small laser devices such as typical semiconductor laser diodes show thermal characteristics even above threshold. In the limit of long time averages represented by the low frequency component of the noise, the same devices exhibit squeezing. It is shown that squeezing and thermal noise can coexist in the multi-mode output field of laser diodes. This result implies that the squeezed light generated by regularly pumped semiconductor laser diodes is qualitatively different from single mode squeezed light. In particular, no entanglement between photons can be generated using this type of collective multi-mode squeezing.

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Holger F. Hofmann, Ortwin Hess. 2000-06-29. Coexistence of thermal noise and squeezing in the intensity fluctuations of small laser diodes. https://doi.org/10.1364/josab.17.001926

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