GENERATION OF INTENSITY-CORRELATED TWIN BEAMS USING SERIES-COUPLED SEMICONDUCTOR-LASERS

The low-frequency intensity noise of high-quantum-efficiency lasers or light-emitting diodes (LED's) is dominated by the pump noise. By coupling two or more semiconductor lasers (or LED's) in series with a current source, the pump noise of the two lasers will be equal, and the intensity noise of the lasers will be highly correlated. It is shown that one may generate sub-Poissonian light by measuring the intensity fluctuations of one of the beams and feeding back (or forward) the information to regulate the other photon beam. The generation scheme is shown to have much in common with intensity-correlated twin beam generation from nondegenerate optical paxametric oscillators.