Analysis of Exciton Absorption Peak Broadening Contributions in InGaAs/InP Multi Quantum Wells

The excitonic absorption of InGaAs/InP multi quantum wells prepared by chemical beam epitaxy with different growth conditions and structure parameters are studied in the temperature range 8 to 300 K and in the spectral region where the heavy hole to electron (hh–e) transition corresponding to n = 1 arises. In particular, a lineshape modelling is attempted using a Gaussian function. The temperature variation of the full width at half maximum (FWHM) is discussed in terms of an intrinsic contribution Γ 0 plus a thermal broadening due to the interaction with longitudinal optical (LO) phonons. The Γ 0 value may be considered as a helpful parameter to investigate the structural quality of the samples studied, leading to the observation that absorption spectroscopy is a simple and powerful characterization technique of MQW.