Indirect to direct exciton transition by laser irradiance in a type II core/shell quantum dot

Effect of laser irradiance on indirect exciton in Type II CdTe/CdSe Core/Shell Quantum Dot (CSQD) is investigated theoretically through diamagnetic susceptibility (chi(dia)). CO2 laser source of wavelength 10 mu m with 30 THz frequency is used as an external perturbation. Using variational method, chi(dia) of exciton is computed for different laser intensity (alpha(0)) under different shell thickness. Drastic variation in chi(dia) is observed on enhancing alpha(0). This is due to the wide spatial extent of the carriers by the high screening effect of LASER. Transition of localized exciton from core to the shell regime is pictured via the probability density function of exciton. Further, the ground state energy of hole and the electron of this CSQD is determined for various shell radius (Rs). It is inferred that the incident of LASER strongly alters the ground state energy of the carriers. The evolution of direct exciton from indirect exciton by laser irradiance is realized. To conclude, the external laser perturbation plays a crucial role in improving the device performance by stabilizing excitonic states.