Abstract :
Remarkably different characteristics were found on isolated and close-packed self-assembled In0.4Ga0.6As/GaAs (311)B quantum dots (QDs). Sub-peaks superimposed on the regular Gaussian photoluminescence (PL) peak were observed in a close-packed QD array, in contrast to the single Gaussian PL peak in an isolated one. A tunneling-current peak in an isolated QD array changes into several equidistant features in a close-packed one. The possible mechanisms of the fine structures are discussed.
