Magnetic field effect on the polarizability of shallow donor in cylindrical quantum dot

Abstract

Using a variational method in the effective mass approximation and considering a noninteracting model, we have calculated the binding energy and the polarizability of shallow donor impurities in cylindrical GaAs quantum dot under an applied magnetic field. We have considered an infinite and finite confinement model to describe the barriers on the dot boundaries. We present our results as function of the size of the dot and several values of the magnetic field strength. It is found that the polarizability decreases as the dot radius R decreases, reaches a minimum at a certain value of R and then increases as the radius becomes smaller. The magnetic field increases the binding energy and strongly reduces the polarizability. The finite barrier-height effects are important for smaller dot widths. For higher field strength and large dot, the magnetic field effects are predominant.