Integral Method Analysis of Electroabsorption Spectra and Its Application to Quantum Dots of PbSe

Abstract

The integral method is proposed to analyze the electroabsorption (E-A) spectra, since the change in the electric dipole moment and/or polarizability following absorption can be determined precisely and the bands buried under strong absorption bands can be confirmed. This method, where not only the observed E-A spectra but also each of their first and second integral spectra are fitted using the absorption and their derivative and integral spectra, has been successfully applied to the E-A spectra of semiconductor quantum dots of PbSe. In the results, one absorption band, which is not identified in the absorption spectrum because of the extremely weak intensity and also showing a remarkable blue shift in the presence of an electric field because of the large difference in polarizability between the ground state and the excited state, has been confirmed to be located between the first and second strong exciton bands. The size dependence of PbSe QDs of the peak position of the newly confirmed band as well as ...