Photoluminescence Studies on Self-Organized InAlAs/AlGaAs Quantum Dots under Pressure

Abstract

The pressure dependence of the low temperature photoluminescence (PL) in self-organized In 0.5 Al 0.5 As/Al 0.25 Ga 0.75 As quantum dots (QD) has been investigated up to 8 GPa. Interesting features of the QD PL observed in our study are: (i) a decrease in the linewidth up to 1.8 GPa, (ii) no significant shift in the PL energy between 0.8 and 2.2 GPa, (iii) anticrossing behavior in the region of 2.2 to 2.6 GPa, and (iv) complete quenching of PL beyond 2.6 GPa. The observed pressure behavior is explained on the basis of the crossing between Γ and X conduction bands.