Quantitative investigations of optical absorption in InAs∕InP(311)B quantum dots emitting at 1.55μm wavelength

Abstract

We have measured the absorbance of InAs∕InP quantum dots emitting at 1.55μm wavelength with a Fourier transform infrared spectrometer. The sample is a 12-stack InAs quantum dots grown by molecular beam epitaxy on (311)BInP oriented substrate. The absorption coefficient is estimated at 4400cm−1 for 3nm height and 5×1010cm−2 surface density. The absorption of the quantum dot structures is found to be similar to quantum well structures when the number of atoms considered absorbing is equivalent. The Stokes shift between the absorbance and the photoluminescence spectra is also investigated at 4 and 293K.