The dielectric response function describes the linear behavior of semiconductors to electric fields that vary with time and space..

The dielectric response function is essential to understanding the wide range of many-body properties of semiconductors, especially for the case of semiconductors that contain combinations of n-type and p-type dopants. As shown below, calculations and interpretations of Raman spectral lines shapes involve the complex dielectric response function that depends on the frequency and wavelength of electric fields. Raman spectra have a number of features that are consequences of the semiconductor band structure and many-body effects. Developing a theory that contains these features in Raman spectra requires accurate calculations of the dielectric response function with many-body effects.