We compare results obtained in several tens of samples grown by molecular-beam epitaxy under different growth conditions with a substantial amount of data found in the literature. By plotting the photoluminescence (PL) peak energy (E-p) of the quantum dot (QD) bands as a function of the nominal thickness of deposited InAs (L) three regions are clearly evidenced in the (E-p,L) plane. Below the so-called critical thickness (L-c), three-dimensional precursors of QD's show a smooth dependence of their emission energy on L. Around L-c, QD's show a steep dependence of E-p on L, independent of the growth conditions. Finally, for L greater than or similar to 2 ML one observes a saturation of the PL energy. This energy assumes only discrete values dependent on the growth conditions, which is attributed to the aggregation of quantum dots with different faceting.
Optical properties of InAs quantum dots: Common trends
1999
Abstract
We compare results obtained in several tens of samples grown by molecular-beam epitaxy under different growth conditions with a substantial amount of data found in the literature. By plotting the photoluminescence (PL) peak energy (E-p) of the quantum dot (QD) bands as a function of the nominal thickness of deposited InAs (L) three regions are clearly evidenced in the (E-p,L) plane. Below the so-called critical thickness (L-c), three-dimensional precursors of QD's show a smooth dependence of their emission energy on L. Around L-c, QD's show a steep dependence of E-p on L, independent of the growth conditions. Finally, for L greater than or similar to 2 ML one observes a saturation of the PL energy. This energy assumes only discrete values dependent on the growth conditions, which is attributed to the aggregation of quantum dots with different faceting.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
