Abstract
We measure the temperature of a 2D electron gas in GaAs from the thermopower of a one-dimensional ballistic constriction, using the Mott relation to confirm the calibration from the electrical conductance. Under hot electron conditions, this technique shows that the power loss by the electrons follows a dependence in the Gruneisen-Bloch regime, as predicted for acoustic phonon emission with a screened piezoelectric interaction. An independent measurement using conventional thermometry based on Shubnikov–de Haas oscillations gives a loss rate. We discuss reasons for this discrepancy.
- Received 23 July 1998
DOI:https://doi.org/10.1103/PhysRevLett.81.3491
©1998 American Physical Society