Optically induced Nernst-Ettinghausen effect in the far infrared and strong magnetic fields in HgTe and InSb

Voltage generation in strong magnetic fields (0 to 6 T) in HgTe and n-InSb under far-infrared illumination is observed. The fine structure of the observed voltage versus the magnetic field is interpreted as being due to transitions between Landau sublevels. A new method of experimental determination of the nature of the observed voltage is presented. It is shown that for both the materials investigated, the observed phenomenon is due to the optically-induced Nernst-Ettinghausen effect. From the qualitative analysis it is concluded that at low temperatures and in quantisizing magnetic fields, the phonon drag is the main process responsible for the observed voltage in both, InSb and HgTe. (author)