Arsenic pressure and spacer layer thickness effects on the optical properties of stacked InAs/InAlAs quantum dot array

Abstract

We report on investigations of InAs/InAlAs/InP stacked quantum dots (QDs). The photoluminescence spectroscopy (PL) and time resolved photoluminescence spectroscopy (TRPL) results, have shown an increase of the radiative life time and an important red shift of the PL band with decreasing the spacer layer thickness. The observed effects are explained as a consequence of the electronic coupling between vertical ordered QIs. The PL results have also shown that the emission from these structures depends not only upon the spacer thickness but also on the arsenic pressure. For spacer layer thickness equal to 10 nm and arsenic pressure equal to 5.5 10 -6 Torr we have a more homogenous organisation of the formed nanowires.

Different regimes of electronic coupling and their influence on exciton recombination in vertically stacked InAs/InP quantum wires

“…If the self-filtering effect is towards small (large) sizes a blue (red) shift of the photoluminescence (PL) spectrum is measured [6][7][8][9], whereas a redshift of the PL spectrum is observed when the electronic coupling increases [2,7,11,12]. A simultaneous and more important consequence of such electronic coupling is the exciton wavefunction delocalization along the growth direction [6,11,[14][15][16][17]. The properties of laser diodes based on this kind of stacked layers can be negatively modified by the above-described effects.…”

Study of optical properties in a cubic quantum dot

“…Photoluminescence studies of self-organized InAlAs/AlGaAs quantum dots under pressure were carried out by Phillips et al (1999). Recently, Hjiri et al (2005) reported the pressure effect on Photoluminescence…”