Wavelength dependence of the modal refractive index in 1.3 μm InGaAsP, AlGaInAs and GaInNAs lasers using high pressure

Abstract

We report the variation of the modal refractive index at threshold with lasing wavelength in 1.3 μm InGaAsP, AlGaInAs and GaInNAs multiple quantum well lasers by measuring mode spectra under pressure up to 15 kbar. It is shown that the decrease of index with lasing wavelength is about 4% on average in the pressure range studied. We also find that the modal refractive index reduces with increasing injection current and is very sensitive to the injection current around laser threshold.