Optical manipulation of photo-induced current in spherical semiconductor quantum dots by optical vortices

In this work, we have investigated the existence of photo-induced current in AlGaAs/GaAs/SiO2 spherically symmetric semiconductor quantum dots by orbital angular momentum carrying twisted light. For the quantum dot structure, the core and shell materials are SiO2 and semiconductor, respectively. Because, the thickness of semiconductor layer is in the scale of nanometre, the structure has quantum mechanical properties. And, the total radius of quantum dot is comparable to the spot size of highly focused twisted laser beam. In that case, we investigate the effect of orbital angular momentum and radial node of twisted light on the induced current and magnetic field in the structure. Furthermore, we calculate dependence of induced current on frequency of the light. The results show that magnitude and direction of the induced current can be manipulated by tuning the parameters: radial node, orbital angular momentum, frequency of light and polarisation vector.