Combined effects of intense THz laser field and applied electric field on binding energy of exciton in GaAs/ GaAlAs finite spherical quantum dot

Abstract

In this paper,we study the combined effects of intense THz laser field and electric field on the ground state binding energy of heavy hole excitons confined in GaAs/ GaAlAs spherical finite quantum dots. The formulation is based on the model of “laser dressed potential” which combines Coulomb interaction and field effect in only one potential as reported in the literature. The calculation is performed by using the variational method in the framework of the single band effective mass theory. Our results show that (i) The laser field increases the electron and hole confinement energy that form the exciton in the QD until they reach a maximum, then they become almost constant for a intense laser field., (ii)the electric field and the laser field lowers the binding energy for all quantum dot radii making the exciton stabilized and clustered near the center of the dot,iii)the laser field increases the spatial extention of exciton but the electric field deacreses it linearly.