SPECTRAL DEPENDENCE OF THE ABSORPTION-COEFFICIENT IN III-V MULTIPLE-QUANTUM-WELL STRUCTURES FROM TRANSMITTED LIGHT-INTENSITY MEASUREMENTS AT A SINGLE-WAVELENGTH

We report the development of a useful and a rather simple experimental technique that can be used to determine the wavelength dependence of the absorption coefficient as a function of electric field in III-V co mpound based multiple quantum well (MQW) devices. In this technique, t he absorption coefficient at some wavelength and applied electric fiel d is extracted from measurement of the transmitted light intensity thr ough the MQW device at a fired wavelength as a function of the applied electric field. Results show good agreement with direct measurements of the absorption coefficient.