Thermopower and Thermomagnetic Effects of Hot Carriers under Conditions of Mutual Electron–Phonon Prag

Abstract

AbstractThe thermopower and the thermomagnetic effects of hot carriers in non‐degenerate semiconductors are studied taking into account both, a mutual drag and heating of the electrons and phonons. The cases when a thermal reservoir for the long‐wavelength phonons is or is not present are considered. It is shown that the mutual drag leads to a strong increase of the thermopower V = Ve + Vp and of the electron part of the Nernst‐Ettingshausen (NE) voltage Ue. Moreover the drag produces a very strong dependence of these effects on an external heating electric field E. For instance if a thermal reservoir is present Ve ≈ E4/3 and Vp ≈ E10/3 under the conditions of electron and phonon strong mutual drag. Presence or absence of the thermal reservoir influences the phonon part of the NE voltage Up essentially. For example in presence of the thermal reservoir Up = 0, while in its absence Up is non‐zero and grows rapidly on raising E: Up ≈ E26/9.