Fluorescence modulation of quantum dots in subsurface defects of optical elements by a linearly polarized light

The limited excitation efficiency of quantum dots in the detection of subsurface defects in optical elements by quantum dot fluorescence gives rise to insufficient accuracy. To enhance the excitation efficiency of quantum dots, we studied the modulation of the polarization direction of linearly polarized incident light on quantum dot fluorescence. We first apply density matrix evolution theory to study the quantum dots interacting with linearly polarized incident light and emitting fluorescence. The fluorescence intensity exhibits cosine oscillations versus modulated laser polarization. It reaches a maximum value at the polarization angle zero, and then decreases as the angle becomes larger until