Effect of the Coulomb interaction on far-infrared absorption in a square-well quantum dot

We calculate far-infrared-absorption spectra and the absorption coefficient of two electrons confined in a square-well quantum dot as the strength of the Coulomb interaction between the electrons is changed. We determine that there are many different types of absorption, some induced by the Coulomb interaction. This is because electrons are confined by a heterostructure of compound semiconductors, so a square-well potential allows the electron-electron interaction to affect the far-infrared-absorption spectra. When a side of the quantum dot becomes larger than 50 nm, one or more types of absorption become much more intense than the others. This suggests that a strong correlation between electrons enhances certain types of absorption.