The effect of substrate growth temperature on the optical properties of self-assembled InAs quantum dots

Summary form only given. We investigate MBE-grown samples of capped InAs quantum dots with substrate growth temperatures ranging from 465/spl deg/C to 515/spl deg/C and explore their optical properties. In our first measurement, we perform low temperature (5K) photoluminescence experiments on ensembles of quantum dots in our samples using 100 /spl mu/w of continuous-wave, 735 nm light from a Ti-sapphire laser for exciting the quantum dots. We find that the photoluminescence emission energy decreases with increasing substrate growth temperature. Our second type of optical experiment involves the time resolution of the optical emission from a pulsed laser source. We retrieve time-resolved data using a Hamamatsu streak-camera with attached monochrometer. Our streakcamera measurements yield color-hue plots of intensity versus wavelength versus time. This allows us to tell not only where in the energy spectrum our quantum dots are emitting, but also for how long they emit. We find that increasing the growth temperature decreases the quantum dot lifetime.