The non-resonant intense laser field effects on the binding energies and the nonlinear optical properties of a donor impurity in Rosen– Morse quantum well

Abstract

We analyze the influence of electron–donor impurity interaction as well as of a high-frequency non-resonant intense laser field on the intraband linear, third-order nonlinear, and total optical absorption coefficients in a GaAs/GaAlAs heterostructure with conduction band Rosen–Morse potential profile. For this, firstly, the binding energies associated with ground and first excited states (1s, 2s) of a hydrogenic donor center have been calculated as functions of the impurity position using the effective-mass approximation and a variational procedure. Then, the linear, third-order nonlinear, and total optical absorption coefficients were evaluated for transitions between the impurity and subband electronic states. Emphasis is made on understanding the role of structure parameters on the features of these nonlinear optical properties. The numerical results show that the impurity binding energies and lowest intersubband transitions depend strongly on the high-frequency intense laser field. The presence of impurity atom causes a blueshift in the optical spectrum and an increase in the amplitude of absorption coefficients. Additionally, it was observed that studied optical transitions are sensitive to the structure parameters and high-frequency intense laser field, thus affecting the optical absorption response.