Anomalous electronic transport in high-mobility Corbino rings.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 37400458.
- Also identified by DOI 10.1038/s41467-023-39526-x and PMC identifier 10318031.
- Licence recorded as CC BY.
- The licence permits redistribution, so the abstract is shown in full and the full text is available from the publisher.
Abstract
We report low-temperature electronic transport measurements performed in two multi-terminal Corbino samples formed in GaAs/Al-GaAs two-dimensional electron gases (2DEG) with both ultra-high electron mobility ( ≳ 20 × 10<sup>6</sup> cm<sup>2</sup>/ Vs) and with distinct electron density of 1.7 and 3.6 × 10<sup>11</sup> cm<sup>-2</sup>. In both Corbino samples, a non-monotonic behavior is observed in the temperature dependence of the resistance below 1 K. Surprisingly, a sharp decrease in resistance is observed with increasing temperature in the sample with lower electron density, whereas an opposite behavior is observed in the sample with higher density. To investigate further, transport measurements were performed in large van der Pauw samples having identical heterostructures, and as expected they exhibit resistivity that is monotonic with temperature. Finally, we discuss the results in terms of various lengthscales leading to ballistic and hydrodynamic electronic transport, as well as a possible Gurzhi effect.