Room‐temperature optical nonlinearities of GaInAs/AlInAs and GaAlInAs/AlInAs multiple quantum wells and integrated‐mirror etalons at 1.3 μm

The room‐temperature nonlinear absorption spectra of a 40 A GaInAs/AlInAs and a 90 A GaAlInAs/AlInAs multiple quantum well (MQW) were measured near 1.3 μm using a pump and probe technique. Saturation carrier densities at the heavy‐hole exciton peak were determined to be 1.2×1018 and 1.0×1018 cm−3 with carrier recovery times of ≂5 ns and ≂750 ps for the two samples, respectively. These measured saturation carrier densities are close to the reported values for GaAs/AlGaAs MQWs. Fabry–Perot etalons with integrated mirrors grown by molecular beam epitaxy with GaInAs/AlInAs MQWs as spacer layers were also fabricated as optical logic gate devices. We demonstrate a 125‐ps recovery time for the etalon switching device at room temperature.