HIGH-SPEED DYNAMICS IN INP BASED MULTIPLE QUANTUM-WELL LASERS

In this paper, the problem of low frequency rolloff and limited bandwidth in long wavelength InP based multiple quantum well (MQW) lasers is discussed by investigating the dependence of resonance frequency and the damping factor on the strain, and structural design of the wells and barriers. To explain the small bandwidth, we use a model of the carrier transport effect with two parts of the carrier density, inside and outside of the quantum wells. The dependence of the K factor on the operating temperature is investigated, and the results of this measurement are found to fully support the proposed carrier transport model. The solutions to this carrier transport problem are discussed. Finally, we propose a measurement method of the intrinsic modulation response free from the carrier transport effect.