Light Absorption by Free Charge Carriers with Scattering Mechanisms in a Semiconductor Superlattice

A theory is presented for the absorption of light by free charge carriers, taking into account the electron-phonon interaction in the semiconductor superlattices in a magnetic field. When the magnetic field is directed perpendicular to the surface of the semiconductor superlattice, the oscillations of the coefficient of the light absorption by free charge carriers in the case of scattering by polar phonons were determined, depending both on the magnetic field induction and on the frequency of the incident light and the resonance condition, within the framework of the second-order excitation theory. The dependence of the normalized coefficient α_pol on hΩ at B = 3, 5, 10 T, as well as the dependence of α_pol,max on the external magnetic field B at the miniband width Δ = 0.0024 eV, is given. The maximum value of α_pol decreases as the external magnetic field increases. The external magnetic field affects the value of α_pol,max and shifts the frequency hΩ towards high frequencies.