EXCESS NOISE OF AN ER YB FIBER SUPERFLUORESCENT RADIATION SOURCE/

A study is made of the noise in the output intensity of a high-power s uperfluorescent fiber radiation source generating 20 mW in the 1.55 mu m region of the spectrum. The source is constructed in an all-fiber t echnology from a quartz fiber activated with ytterbium and erbium. It is found that the spectral density of the noise in the frequency range 100-500 kHz is uniform and corresponds to the excess noise of ''therm al'' sources. It is shown that the noise in the output intensity of th e source can be compensated (decreased by an order of magnitude) in a two-channel scheme of photodetection, where it approaches a level clos e to the photon shot noise. (C) 1997 American Institute of Physics. [S 1063-7850(97)00112-2].