Non-Ohmic to Ohmic Crossover in the Breakdown of the Quantum Hall States in Graphene under Broadband Excitations
Year: 2026
Type: article
Abstract: Graphene, through the coexistence of large cyclotron gaps and small spin and valley gaps, offers the possibility to study the breakdown of the quantum Hall effect (QHE) across a wide range of energy scales. In this Letter, we investigate the breakdown of the QHE in high-mobility graphene Corbino devices under broadband excitation ranging from dc up to 10 GHz. We find that the conductance is consistently described by variable range hopping (VRH) and extract the hopping energies from both temperature- and field-driven measurements. Using VRH thermometry, we can distinguish between non-Ohmic and Ohmic regimes of bulk conduction, which are dominated by electric-field-assisted VRH and Joule heating, respectively. Our results demonstrate that the breakdown in the quantum Hall regime of graphene is governed by a crossover from non-Ohmic, field-driven VRH to Ohmic, Joule-heating-dominated transport.
Source: Physical Review Letters
DOI: 10.1103/5kkx-rcdh
Institutions: University of Cologne, Centre National de la Recherche Scientifique, Commissariat à l'Énergie Atomique et aux Énergies Alternatives, Université Paris-Saclay, CEA Paris-Saclay - Etablissement de Saclay, Service de Physique de l'État Condensé, CEA Paris-Saclay, National Institute for Materials Science, Research Center for Materials Nanoarchitectonics, Université Paris Cité, Université Paris Sciences et Lettres, École Normale Supérieure - PSL, Sorbonne Université
Language: English
Subfield: Atomic and Molecular Physics, and Optics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: green
Funders: Deutsche Forschungsgemeinschaft, Agence Nationale de la Recherche, Ministry of Education, Culture, Sports, Science and Technology, Laboratoire d’excellence Physique Atomes Lumière Matière, European Research Council, Japan Society for the Promotion of Science, Japan Science and Technology Agency, Core Research for Evolutional Science and Technology
OpenAlex ID: W4415849616