Effect of a static electric field on the optical spectrum of a quantum dot

The energy levels and the optical absorption of a circular quantum dot with hard walls are studied in the presence of a static electric field. The results are compared with the case of soft-wall confinement. Calculations show that: (i) the structures of the energy levels of the two cases are different, therefore their absorption varies accordingly; (ii) the nonlinear term has a significant contribution to the total optical absorption coefficient.