Magnetic field effect on the linear and nonlinear refractive index and optical absorption of a donor in a GaAs quantum ring

Abstract

Abstract The effects of the magnetic field (γ), the radial position of impurity and the degree of confinement on the oscillator strength (OS), refractive index and optical absorption (α) of an impurity inside a GaAs quantum ring (QR) are explored using the effective mass approximation and variational method. It is shown that the peak position of the optical absorption and the refractive index decrease and move toward the lower incident photon energy as the strength of the γ increases. In addition, it is found that the strongest α relates to the case when the impurity is positioned at the right side of QR in the presence of the magnetic field. Our examinations also show that the oscillator strength decreases as the γ increases especially for an on-center donor impurity.