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Title: Disentangling the surface and bulk electronic structures of LaOFeAs

Abstract

We performed a comprehensive angle-resolved photoemission spectroscopy study of the electronic band structure of LaOFeAs single crystals. We found that samples cleaved at low temperature show an unstable and very complicated band structure, whereas samples cleaved at high temperature exhibit a stable and clearer electronic structure. Using in situ surface doping with K and supported by first-principles calculations, we identify both surface and bulk bands. Our assignments are confirmed by the difference in the temperature dependence of the bulk and surface states.

Authors:
 [1];  [1];  [2];  [1];  [3];  [3];  [1];  [4];  [2];  [2]
  1. Chinese Academy of Sciences (CAS), Beijing (China)
  2. Chinese Academy of Sciences (CAS), Beijing (China); Collaborative Innovation Center of Quantum Matter, Beijing (China)
  3. Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Advanced Light Source (ALS)
  4. Chinese Academy of Sciences (CAS), Beijing (China); Collaborative Innovation Center of Quantum Matter, Beijing (China); Purdue Univ., West Lafayette, IN (United States)
Publication Date:
Research Org.:
Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)
Sponsoring Org.:
USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22)
OSTI Identifier:
1393076
Grant/Contract Number:
AC02-05CH11231
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Physical Review B
Additional Journal Information:
Journal Volume: 94; Journal Issue: 10; Journal ID: ISSN 2469-9950
Publisher:
American Physical Society (APS)
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY

Citation Formats

Zhang, P., Ma, J., Qian, T., Shi, Y. G., Fedorov, A. V., Denlinger, J. D., Wu, X. X., Hu, J. P., Richard, P., and Ding, H. Disentangling the surface and bulk electronic structures of LaOFeAs. United States: N. p., 2016. Web. doi:10.1103/PhysRevB.94.104517.
Zhang, P., Ma, J., Qian, T., Shi, Y. G., Fedorov, A. V., Denlinger, J. D., Wu, X. X., Hu, J. P., Richard, P., & Ding, H. Disentangling the surface and bulk electronic structures of LaOFeAs. United States. doi:10.1103/PhysRevB.94.104517.
Zhang, P., Ma, J., Qian, T., Shi, Y. G., Fedorov, A. V., Denlinger, J. D., Wu, X. X., Hu, J. P., Richard, P., and Ding, H. 2016. "Disentangling the surface and bulk electronic structures of LaOFeAs". United States. doi:10.1103/PhysRevB.94.104517. https://www.osti.gov/servlets/purl/1393076.
@article{osti_1393076,
title = {Disentangling the surface and bulk electronic structures of LaOFeAs},
author = {Zhang, P. and Ma, J. and Qian, T. and Shi, Y. G. and Fedorov, A. V. and Denlinger, J. D. and Wu, X. X. and Hu, J. P. and Richard, P. and Ding, H.},
abstractNote = {We performed a comprehensive angle-resolved photoemission spectroscopy study of the electronic band structure of LaOFeAs single crystals. We found that samples cleaved at low temperature show an unstable and very complicated band structure, whereas samples cleaved at high temperature exhibit a stable and clearer electronic structure. Using in situ surface doping with K and supported by first-principles calculations, we identify both surface and bulk bands. Our assignments are confirmed by the difference in the temperature dependence of the bulk and surface states.},
doi = {10.1103/PhysRevB.94.104517},
journal = {Physical Review B},
number = 10,
volume = 94,
place = {United States},
year = 2016,
month = 9
}

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