Interface-related band-bending effects on intersubband transitions in doped single quantum wells

We show that band-bending corrections related to the existence of nonabrupt interfaces can change considerably the electron intersubband transitions in modulation-doped single quantum wells. In our calculations, the position-dependent electron effective mass in the interface regions is taken into account, and the Poisson and Schrödinger equations for the single quantum wells are solved self-consistently. When the doping density in the barriers is , we obtain that the first electron intersubband transition energy in a 100 Å single quantum well with nonabrupt interface widths of only 12 Å is higher than the one calculated for a similarly doped abrupt well.