Nonlinear optical properties of GaN/AlN constant total effective radius multi-wells quantum rings

Abstract

In this study, we investigate the effect of the number of wells and ring thickness on the third-order absorption coefficient as well as figure dipole matrix elements and oscillator strength of multi-wells GaN / AlN constant total effective radius multi-wells quantum rings (CTER-MWQRs). We show that order of the nonlinearity decreases by increasing of the number of wells by going from 1 to 2 numbers of wells and increases by going from 2 to 10 numbers of wells. This is just against the effect of the inner quantum ring radius R0 values, since order of the nonlinearity increases by increasing of the R0 value by going from 0 nm to 5 nm and decreases by going from 5 nm to 30 nm for an eight wells CTER-MWQRs. Finally, we prove that, if we want to construct a system which has a special peak position, changing of the R0 values is more efficient than changing of the number of wells.