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Title: Magnetic field tuning of an excitonic insulator between the weak and strong coupling regimes in quantum limit graphite [Tunable excitonic insulator in quantum limit graphite]

Abstract

Here, the excitonic insulator phase has long been predicted to form in proximity to a band gap opening in the underlying band structure. The character of the pairing is conjectured to crossover from weak (BCS-like) to strong coupling (BEC-like) as the underlying band structure is tuned from the metallic to the insulating side of the gap opening. Here we report the high-magnetic field phase diagram of graphite to exhibit just such a crossover. By way of comprehensive angle-resolved magnetoresistance measurements, we demonstrate that the underlying band gap opening occurs inside the magnetic field-induced phase, paving the way for a systematic study of the BCS-BEC-like crossover by means of conventional condensed matter probes.

Authors:
 [1];  [2];  [3];  [4];  [5];  [2]; ORCiD logo [2]
  1. Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Huazhong Univ. of Science and Technology, Wuhan (China)
  2. Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
  3. Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Florida State Univ., Tallahassee, FL (United States)
  4. Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Cornell Univ., Ithaca, NY (United States)
  5. Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Max Planck Institute for Chemical Physics of Solids, Presden (Germany)
Publication Date:
Research Org.:
Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
Sponsoring Org.:
USDOE
OSTI Identifier:
1375160
Alternate Identifier(s):
OSTI ID: 1409794
Report Number(s):
LA-UR-14-29680; LA-UR-17-30078
Journal ID: ISSN 2045-2322
Grant/Contract Number:
AC52-06NA25396
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Scientific Reports
Additional Journal Information:
Journal Volume: 7; Journal Issue: 1; Journal ID: ISSN 2045-2322
Publisher:
Nature Publishing Group
Country of Publication:
United States
Language:
English
Subject:
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; 36 MATERIALS SCIENCE; High Magnetic Field Science

Citation Formats

Zhu, Zengwei, McDonald, R. D., Shekhter, A., Ramshaw, B. J., Modic, K. A., Balakirev, F. F., and Harrison, N.. Magnetic field tuning of an excitonic insulator between the weak and strong coupling regimes in quantum limit graphite [Tunable excitonic insulator in quantum limit graphite]. United States: N. p., 2017. Web. doi:10.1038/s41598-017-01693-5.
Zhu, Zengwei, McDonald, R. D., Shekhter, A., Ramshaw, B. J., Modic, K. A., Balakirev, F. F., & Harrison, N.. Magnetic field tuning of an excitonic insulator between the weak and strong coupling regimes in quantum limit graphite [Tunable excitonic insulator in quantum limit graphite]. United States. doi:10.1038/s41598-017-01693-5.
Zhu, Zengwei, McDonald, R. D., Shekhter, A., Ramshaw, B. J., Modic, K. A., Balakirev, F. F., and Harrison, N.. Thu . "Magnetic field tuning of an excitonic insulator between the weak and strong coupling regimes in quantum limit graphite [Tunable excitonic insulator in quantum limit graphite]". United States. doi:10.1038/s41598-017-01693-5. https://www.osti.gov/servlets/purl/1375160.
@article{osti_1375160,
title = {Magnetic field tuning of an excitonic insulator between the weak and strong coupling regimes in quantum limit graphite [Tunable excitonic insulator in quantum limit graphite]},
author = {Zhu, Zengwei and McDonald, R. D. and Shekhter, A. and Ramshaw, B. J. and Modic, K. A. and Balakirev, F. F. and Harrison, N.},
abstractNote = {Here, the excitonic insulator phase has long been predicted to form in proximity to a band gap opening in the underlying band structure. The character of the pairing is conjectured to crossover from weak (BCS-like) to strong coupling (BEC-like) as the underlying band structure is tuned from the metallic to the insulating side of the gap opening. Here we report the high-magnetic field phase diagram of graphite to exhibit just such a crossover. By way of comprehensive angle-resolved magnetoresistance measurements, we demonstrate that the underlying band gap opening occurs inside the magnetic field-induced phase, paving the way for a systematic study of the BCS-BEC-like crossover by means of conventional condensed matter probes.},
doi = {10.1038/s41598-017-01693-5},
journal = {Scientific Reports},
number = 1,
volume = 7,
place = {United States},
year = {Thu May 04 00:00:00 EDT 2017},
month = {Thu May 04 00:00:00 EDT 2017}
}

Journal Article:
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