Linear and nonlinear optical properties of semiconductor nanorings with magnetic field and disorder - Influence on excitons and biexcitons

Abstract

Linear and nonlinear optical absorption spectra are studied theoretically for semiconductor nanorings penetrated by a magnetic field. Due to the Aharanov-Bohm effect the spectral position as well as the oscillator strength of the exciton change periodically as function of the magnetic flux enclosed by the ring. In the nonlinear differential absorption spectra it is found that the magnetic field strongly modifies Coulomb many-body correlations. In particular, the magnetic-field-induced increase of the exciton binding energy is accompanied by a decrease of the biexciton binding energy. The persistence of these effects in the presence of energetic disorder is analyzed.

PACS

71.35.Cc Intrinsic properties of excitons; optical absorption spectra – 78.66.-w Optical properties of specific thin films – 42.50.Md Optical transient phenomena: quantum beats, photon echo, free-induction decay, dephasings and revivals, optical nutation, and self-induced transparency – 03.65.Bz Foundations, theory of measurement, miscellaneous theories