We have performed theoretical calculation of second-order nonlinear optical rectification (OR) coefficient in a typical GaAs/AlGaAs QD with ellipsoidal confinement potential in the presence of an impurity and an applied electric field. Using an appropriate coordinate transformation and the perturbation theory, we have investigated the OR coefficient as a function of incident photon energy. Calculation results show that the values of OR coefficient increase with an increase of applied electric field. However, the values decrease with increases in confinement strength and ellipticity constant. Additionally, the presence of a donor impurity shifts the OR coefficient peak positions to higher energies (blueshift), contrary to that of an acceptor impurity. (C) 2011 Elsevier B.V. All rights reserved.
机构:
Univ Bucharest, Fac Phys, POB MG 11,Str Atomistilor 405, Bucharest 077125, RomaniaUniv Bucharest, Fac Phys, POB MG 11,Str Atomistilor 405, Bucharest 077125, Romania