KIT | KIT-Bibliothek | Impressum | Datenschutz

Vanishing Thermal Equilibration for Hole-Conjugate Fractional Quantum Hall States in Graphene

Srivastav, Saurabh Kumar; Kumar, Ravi; Spånslätt, Christian 1,2; Watanabe, K.; Taniguchi, T.; Mirlin, Alexander D. 1,2; Gefen, Yuval 2; Das, Anindya
1 Institut für Theorie der Kondensierten Materie (TKM), Karlsruher Institut für Technologie (KIT)
2 Institut für Quantenmaterialien und -technologien (IQMT), Karlsruher Institut für Technologie (KIT)

Abstract (englisch):
Transport through edge channels is responsible for conduction in quantum Hall (QH) phases. Robust quantized values of charge and thermal conductances dictated by bulk topology appear when equilibration processes become dominant. We report on measurements of electrical and thermal conductances of integer and fractional QH phases, realized in hexagonal boron nitride encapsulated graphite-gated bilayer graphene devices for both electron and hole doped sides with different valley and orbital symmetries. Remarkably, for complex edges at filling factors ν=53 and 83, closely related to the paradigmatic hole-conjugate ν=23 phase, we find quantized thermal conductance whose values (3κ0T and 4κ0T, respectively where κ0T is the thermal conductance quantum) are markedly inconsistent with the values dictated by topology (1κ0T and 2κ0T, respectively). The measured thermal conductance values remain insensitive to different symmetries, suggesting its universal nature. Our findings are supported by a theoretical analysis, which indicates that, whereas electrical equilibration at the edge is established over a finite length scale, the thermal equilibration length diverges for strong electrostatic interaction. ... mehr

DOI: 10.1103/PhysRevLett.126.216803
Zitationen: 12
Zitationen: 18
Zugehörige Institution(en) am KIT Institut für Quantenmaterialien und -technologien (IQMT)
Institut für Theorie der Kondensierten Materie (TKM)
Publikationstyp Zeitschriftenaufsatz
Publikationsmonat/-jahr 05.2021
Sprache Englisch
Identifikator ISSN: 0031-9007, 1079-7114
KITopen-ID: 1000133721
HGF-Programm 47.12.01 (POF IV, LK 01) Advanced Solid-State Qubits and Qubit Systems
Erschienen in Physical review letters
Verlag American Physical Society (APS)
Band 126
Heft 21
Seiten 216803
Vorab online veröffentlicht am 27.05.2021
Nachgewiesen in Dimensions
Web of Science
KIT – Die Forschungsuniversität in der Helmholtz-Gemeinschaft
KITopen Landing Page