Abstract
We report experiments on the effect of a parallel magnetic field on the thermopower of a double quantum well over the field range at temperatures of . The main feature of interest is the effect on the thermopower of the anti-crossing of the dispersion curves of the electrons in each well. At low temperatures, where diffusion effects dominate the thermopower, the results are generally in accord with previous theoretical predictions, though the magnitude of the observed effects is much smaller due to impurity and thermal broadening of the electronic energy levels. In this regime we show that the thermopower results can be quantitatively related to the derivative of the observed resistivity with respect to magnetic field. At high temperatures, where phonon drag is dominant, the behavior of the thermopower at the anti-crossing closely resembles that of the resistivity.
- Received 14 May 2004
DOI:https://doi.org/10.1103/PhysRevB.70.155333
©2004 American Physical Society