Emptying Dirac valleys in bismuth using high magnetic fields

Abstract : The Fermi surface of elemental bismuth consists of three small rotationally equivalent electron pockets, offering a valley degree of freedom to charge carriers. A relatively small magnetic field can confine electrons to their lowest Landau level. This is the quantum limit attained in other dilute metals upon application of sufficiently strong magnetic field. Here we report on the observation of another threshold magnetic field never encountered before in any other solid. Above this field, B empty , one or two valleys become totally empty. Drying up a Fermi sea by magnetic field in the Brillouin zone leads to a manyfold enhancement in electric conductance. We trace the origin of the large drop in magnetoresistance across B empty to transfer of carriers between valleys with highly anisotropic mobilities. The non-interacting picture of electrons with field-dependent mobility explains most results but the Coulomb interaction may play a role in shaping the fine details.
Type de document :
Article dans une revue
Nature Communications, Nature Publishing Group, 2017, 8, pp.15297. 〈10.1038/ncomms15297〉
Liste complète des métadonnées

http://hal.upmc.fr/hal-01534749
Contributeur : Gestionnaire Hal-Upmc <>
Soumis le : jeudi 8 juin 2017 - 10:54:00
Dernière modification le : jeudi 11 janvier 2018 - 06:28:16
Document(s) archivé(s) le : samedi 9 septembre 2017 - 12:18:48

Fichier

ncomms15297.pdf
Publication financée par une institution

Licence


Distributed under a Creative Commons Paternité 4.0 International License

Identifiants

Collections

Citation

Zengwei Zhu, Jinhua Wang, Huakun Zuo, Benoît Fauqué, Ross D. Mcdonald, et al.. Emptying Dirac valleys in bismuth using high magnetic fields. Nature Communications, Nature Publishing Group, 2017, 8, pp.15297. 〈10.1038/ncomms15297〉. 〈hal-01534749〉

Partager

Métriques

Consultations de la notice

85

Téléchargements de fichiers

56