Optical Polarization Properties of InAs/GaAs Quantum Dot Semiconductor Optical Amplifier

We have investigated cleaved-edge photoluminescence (PL) polarization properties of InAs/GaAs quantum dot (QD) traveling-type semiconductor optical amplifiers (SOAs). Transverse-electric (TE) and transverse magnetic (TM) mode PL intensities of the devices have been examined. TE-mode PL intensity of QD-SOA is observed to be much stronger than TM-mode. The results indicate that the valence band edge of the QDs is heavy-hole like. Temperature dependence on the PL polarization properties of QD-SOA has been carried out and analyzed. It is observed that an enhancement of TM-mode PL intensity of QD-SOA at higher temperature is due to the fact that the inhomogeneous thermal strain induced effect.