skip to main content

DOE PAGESDOE PAGES

Title: Emptying Dirac valleys in bismuth using high magnetic fields

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 in this paper 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.
Authors:
 [1] ;  [2] ;  [2] ;  [3] ;  [4] ;  [5] ;  [6]
  1. Huazhong Univ. of Science and Technology, Wuhan (China). Wuhan National High Magnetic Field Center and School of Physics; Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
  2. Huazhong Univ. of Science and Technology, Wuhan (China). Wuhan National High Magnetic Field Center and School of Physics
  3. Lab. of Physics and Study of Materials (LPEM, ESPCI), Paris (France); College de France, Paris (France)
  4. Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
  5. Univ. of Electro-Communications, Chofu, Tokyo (Japan). Dept. of Engineering Science
  6. Huazhong Univ. of Science and Technology, Wuhan (China). Wuhan National High Magnetic Field Center and School of Physics; Lab. of Physics and Study of Materials (LPEM, ESPCI), Paris (France)
Publication Date:
Report Number(s):
LA-UR-17-22096
Journal ID: ISSN 2041-1723
Grant/Contract Number:
AC52-06NA25396; 11574097; 2016YFA0401704; 20120772; 16K05437; 15KK0155; 15H02108
Type:
Accepted Manuscript
Journal Name:
Nature Communications
Additional Journal Information:
Journal Volume: 8; Journal ID: ISSN 2041-1723
Publisher:
Nature Publishing Group
Research Org:
Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
Sponsoring Org:
USDOE Laboratory Directed Research and Development (LDRD) Program; USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; High Magnetic Field Science; High Magnetic Fields Quantum-limit
OSTI Identifier:
1361485