Dissipation without resistance: Imaging impurities at quantum Hall edges
Abstract
Motivated by a recent experiment [A. Marguerite et al., Nature (London) 575, 628 (2019), 10.1038/s41586-019-1704-3] on imaging in graphene samples, we investigate theoretically the dissipation induced by resonant impurities in the quantum Hall regime. The impurity-induced forward scattering of electrons at quantum Hall edges leads to an enhanced phonon emission, which reaches its maximum when the impurity state is tuned to resonance by a scanning tip voltage. Our analysis of the effect of the tip potential on the dissipation reveals peculiar thermal rings around the impurities, consistent with experimental observations. Remarkably, this impurity-induced dissipation reveals nontrivial features that are unique for chiral one-dimensional systems such as quantum Hall edges. First, the dissipation is not accompanied by the generation of resistance. Second, this type of dissipation is highly nonlocal: A single impurity induces heat transfer to phonons along the whole edge.
- Publication:
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Physical Review Research
- Pub Date:
- March 2020
- DOI:
- 10.1103/PhysRevResearch.2.013337
- arXiv:
- arXiv:1908.05035
- Bibcode:
- 2020PhRvR...2a3337Z
- Keywords:
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- Condensed Matter - Mesoscale and Nanoscale Physics
- E-Print:
- 10 pages, 3 figures