Semiconductor quantum dots: theory and phenomenology

Abstract

Research in semiconductor quantum dots (q-dots) has burgeoned in the past decade. The size (R) of these q-dots ranges from 1 to 100 nm. Based on the theoretical calculations, we propose energy and length scales which help in clarifying the physics of this mesoscopic system. Some of these length scales are: the Bohr exciton radius (αB*), the carrier de Broglie and diffusion length (λD and lD), the polaron radius (αp), and the reduction factor modulating the optical matrix element (Mx). R < αB is an individual particle confinement regime, whereas the larger ones are exciton confinement regime wherein Coulomb interaction play an important role. Similarly a size-dependent dielectric constant ε(R) should be used for R < αp