Modeling of the second harmonic generation in a lens-shaped InAs/GaAs quantum core/shell dot under temperature, pressure and applied electric field effects

•Lens-shaped InAs/GaAs quantum core/shell.•Enhancement of the second harmonic generation (SHG).•Structure dimensions, pressure and temperature effects are investigated.•Also, the transverse electric field effect on SHG is explored.•As well, a detailed and comprehensive study of the SHG is done within the framework of the compact density-matrix approach and the finite difference method. In this paper, we explore the second harmonic generation (SHG) in a lens-shaped InAs/GaAs quantum core/shell (LSQCS). The three-dimensional Schrödinger equation is given under the framework of the effective mass approximation and it is solved by using the Finite Difference Method (FDM). In this work, we have studied the effects of the structure dimensions, the applied transverse electric field, the hydrostatic pressure and the temperature on the SHG. Obtained results show that the SHG coefficient experiences an obvious red shift and an increase in magnitude with increasing the core radius. Therefore, we note that the SHG experiences a blue shift (red shift) with increasing temperature (pressure). Moreover, both resonant peaks values of the SHG are not a monotonic function of the applied electric field. Thus, SHG reaches its optimized magnitude at a low electric field intensity which is directed along one side of the cross section of the structure under investigation. Finally, at a low electric field intensity, a comparative analysis has shown that the SHG magnitude in LSQCS was 22% higher than that of the uncapped single quantum dot (SQD and a red shift has occurred.