Abstract
We report thermopower measurements in dilute two-dimensional holes subjected to an in-plane magnetic field that drives the system through a metal-insulator transition (MIT). The diffusion thermopower decreases linearly with temperature at low for both low-mobility and high-mobility directions, as expected for metallic systems. At high , in the insulating phase, changes sign along , while drops to zero along . This behavior suggests that the system does not undergo any ground-state modification but, rather, that the apparent MIT transition is accompanied by a dramatic change in the dominant scattering mechanisms.
- Received 9 August 2007
DOI:https://doi.org/10.1103/PhysRevB.76.161307
©2007 American Physical Society