Third-order nonlinear optical effect in semiconductor quantum wells

Third-order optical nonlinearities in semi-parabolic quantum wells are studied. The third-harmonic generation coefficient is obtained by using compact-density-matrix approach and iterative method, and the numerical results are presented for spical semi-parabolic quantum wells. The very large third-harmonic-generation coefficient is obtained in this semi-parabolic quantum wells and it is over 10 times bigger than that obtained in parabolic quantum wells. In addition, the relations among the third-harmonic-generation coefficient, the photons energy, the parabolic confinement frequency, and the relaxation constant are also investigated, respectively.