OPTIMIZATION OF NONLINEAR-OPTICAL RECTIFICATION IN QUANTUM-WELLS USING THE SUPERSYMMETRIC QUANTUM-MECHANICS

A systematic procedure is proposed for optimized design of semiconduct or quantum well structures that provide maximal values of the resonant optical rectification coefficient. It relies on employing supersymmet ric quantum mechanics to vary the starting potential in the isospectra l manner, via the variation of a single scalar parameter, in search of the largest available value of the appropriate product of matrix elem ents (difference of permanent moments times the transition dipole mome nt squared, in this instance). An example design of the structure matc hed for the optical rectification of 10.6 mu m (CO2 laser) radiation i s presented. It starts from the truncated parabolic potential and deli vers a rectification coefficient in excess of the best value reported in the literature. The possibility of realization of optimized structu res is also discussed. (C) 1997 Elsevier Science B.V.