Impurity-related nonlinear optical rectification in double quantum dot under electric field

- Impurity-related optical rectification in double quantum dot under electric field is studied.
- Energies of the first four electron-impurity states present anticrossing at some critical field.
- The binding energy of the ground state varies strongly with the impurity position.
- Optical rectification spectra are sensitive to impurity position and electric field intensity.
- Red or blue shift of resonant peaks are induced by changes in field intensity or impurity position.

The characteristics of donor-impurity-related nonlinear optical rectification in asymmetric double quantum dot under electric field are investigated within the compact density-matrix formalism and the effective mass approximation. The results show that: (i) the binding energy of the ground state varies strongly with the impurity position and it is raised or decreased by the applied field, depending on the impurity position; (ii) the optical rectification spectra are rather sensitive to the impurity position and the electric field intensity; (iii) the changes in the impurity position within the double quantum dot and the electric field value may induce red or blue shift of the resonant peaks of the nonlinear optical rectification.