Laser-power stabilization using a quantum-well modulator

A novel method for laser-power stabilization using a multiple quantum-well reflection electroabsorption modulator with a Fabry-Perot cavity is demonstrated. Stable operation of the modulator produces a linear relationship between control current and optical absorption which permits the realization of noninterferometric optical subtraction and the implementation of a negative feedback architecture. Using this stabilization technique and a modulator with a 70% reflectivity change, intensity noise as large as ±75% of the incident level can be eliminated from a noisy laser beam