Abstract

The quaternary alloy semiconductors such as GaInAsP are of interest for a number of optoelectronic applications at wavelengths compatible with low loss/minimum dispersion optical fibres. Such applications include lasers and detectors, and they are also possible candidates for nonlinear elements exhibiting optical bistability. Here we report excite-probe absorption saturation measurements in 0.86eV band gap GaInAsP using high power, 5psec (fwhm) pulses at 1.176eV and demonstrate that the optical response of this alloy semiconductor can be extremely fast, ~10psec for excited carrier concentrations in excess of 5×10¹⁹cm^-3. This very short timescale is consistent with Auger carrier recombination in this material. Evidence of induced intervalence band absorption is also apparent at high excitation levels. Both of these mechanisms have been proposed as possible reasons for the strong temperature dependence of the threshold currents of 1.3 - 1.55μm wavelength injection lasers made from this alloy^1-3.

© 1984 Optical Society of America