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Title: Precise quantization of anomalous Hall effect near zero magnetic field

Abstract

In this study, we report a nearly ideal quantum anomalous Hall effect in a three-dimensional topological insulator thin film with ferromagnetic doping. Near zero applied magnetic field we measure exact quantization in the Hall resistance to within a part per 10,000 and a longitudinal resistivity under 1 Ω per square, with chiral edge transport explicitly confirmed by nonlocal measurements. Deviations from this behavior are found to be caused by thermally activated carriers, as indicated by an Arrhenius law temperature dependence. Using the deviations as a thermometer, we demonstrate an unexpected magnetocaloric effect and use it to reach near-perfect quantization by cooling the sample below the dilution refrigerator base temperature in a process approximating adiabatic demagnetization refrigeration.

Authors:
 [1];  [1];  [2];  [2];  [2];  [1]
  1. Stanford Univ., Stanford, CA (United States); SLAC National Accelerator Lab., Menlo Park, CA (United States)
  2. Univ. of California, Los Angeles, CA (United States)
Publication Date:
Research Org.:
SLAC National Accelerator Lab., Menlo Park, CA (United States)
Sponsoring Org.:
USDOE Office of Science (SC)
OSTI Identifier:
1177765
Report Number(s):
SLAC-PUB-16247
Journal ID: ISSN 0031-9007; PRLTAO; arXiv:1412.3189
DOE Contract Number:  
AC02-76SF00515
Resource Type:
Journal Article
Journal Name:
Physical Review Letters
Additional Journal Information:
Journal Volume: 114; Journal Issue: 18; Journal ID: ISSN 0031-9007
Publisher:
American Physical Society (APS)
Country of Publication:
United States
Language:
English
Subject:
MATSCI

Citation Formats

Bestwick, A. J., Fox, E. J., Kou, Xufeng, Pan, Lei, Wang, Kang L., and Goldhaber-Gordon, D. Precise quantization of anomalous Hall effect near zero magnetic field. United States: N. p., 2015. Web. doi:10.1103/PhysRevLett.114.187201.
Bestwick, A. J., Fox, E. J., Kou, Xufeng, Pan, Lei, Wang, Kang L., & Goldhaber-Gordon, D. Precise quantization of anomalous Hall effect near zero magnetic field. United States. doi:10.1103/PhysRevLett.114.187201.
Bestwick, A. J., Fox, E. J., Kou, Xufeng, Pan, Lei, Wang, Kang L., and Goldhaber-Gordon, D. Mon . "Precise quantization of anomalous Hall effect near zero magnetic field". United States. doi:10.1103/PhysRevLett.114.187201. https://www.osti.gov/servlets/purl/1177765.
@article{osti_1177765,
title = {Precise quantization of anomalous Hall effect near zero magnetic field},
author = {Bestwick, A. J. and Fox, E. J. and Kou, Xufeng and Pan, Lei and Wang, Kang L. and Goldhaber-Gordon, D.},
abstractNote = {In this study, we report a nearly ideal quantum anomalous Hall effect in a three-dimensional topological insulator thin film with ferromagnetic doping. Near zero applied magnetic field we measure exact quantization in the Hall resistance to within a part per 10,000 and a longitudinal resistivity under 1 Ω per square, with chiral edge transport explicitly confirmed by nonlocal measurements. Deviations from this behavior are found to be caused by thermally activated carriers, as indicated by an Arrhenius law temperature dependence. Using the deviations as a thermometer, we demonstrate an unexpected magnetocaloric effect and use it to reach near-perfect quantization by cooling the sample below the dilution refrigerator base temperature in a process approximating adiabatic demagnetization refrigeration.},
doi = {10.1103/PhysRevLett.114.187201},
journal = {Physical Review Letters},
issn = {0031-9007},
number = 18,
volume = 114,
place = {United States},
year = {2015},
month = {5}
}