1/f Optical Fluctuations In Quantum Well Laser Diodes

Abstract

Electrical and optical intensity noise in quantum well lasers has been investigated. The voltage and optical noise spectra show at low frequencies a 1/f noise contribution and a plateau at high frequencies. The coherence function at low frequencies between optical intensity and voltage noise is close to 1. With the coherence function we split optical noise in two parts. One part is fully correlated to electrical noise and has 1/f shape. The other part has a flat spectrum, which is somewhat higher than the photo detector shot noise. The 1/f optical noise dependence on detector current is in agreement with formerly published experimental results and models.