Electronic and optical properties of InAs/InP quantum dots on InP(100) and InP(311)B substrates: Theory and experiment

摘要

We study the electronic and optical properties of InAs/InP quantum dots (QDs) on (100) and (311)5 substrates. Atomic force microscopy (AFM) and cross-sectional scanning tunneling microscopy (X-STM) are used to define the size and shape of the quantum dots for calculations. Eight-band k·p calculations including strain and piezoelectric effects are then performed on such a structure for two different kinds of substrate orientation (311)B and (100). Results for several QD heights found on (311)S substrate fit well the experimental data obtained from photoluminescence measurements. On (311)B substrate, the shear and hydrostatic deformations are found to be enhanced compared to those on (100) substrate thus affecting the electronic and optical properties. The (31 1)B QDs are found to activate second-order (S-P channels) transitions resulting from the complete loss of symmetry due to the presence of the piezoelectric field.