NONLINEAR-OPTICAL RECTIFICATION IN PARABOLIC QUANTUM-WELLS WITH AN APPLIED ELECTRIC-FIELD

Optical rectification in parabolic quantum wells, with an applied elec tric field, due to resonant intersubband transitions is analyzed using a compact density-matrix approach. The large dipolar matrix elements obtained in such structures are partly due to the small effective mass es of the host materials and are interpreted in terms of the participa tion of the whole band structure in the optical transitions. The other origin of the large optical rectification coefficient lies in the pos sibility of tuning independently the frequency coo of the parabolic po tential and the applied electric field F.