Abstract
Specific heat has had an important role in the study of superfluidity and superconductivity, and could provide important information about the fractional quantum Hall effect as well. However, traditional measurements of the specific heat of a two-dimensional electron gas are difficult due to the large background contribution of the phonon bath, even at very low temperatures. Here, we report measurements of the specific heat per electron in the second Landau level by measuring the thermalization time between the electrons and phonons. We observe the activated behavior of the specific heat of the and fractional quantum Hall states, and extract the entropy by integrating over temperature. Our results are in excellent agreement with previous measurements of the entropy via longitudinal thermopower. Extending the technique to lower temperatures could lead to the detection of the non-Abelian entropy predicted for bulk quasiparticles at filling.
- Received 30 June 2016
DOI:https://doi.org/10.1103/PhysRevB.95.201306
©2017 American Physical Society