Precise quantization of the anomalous hall effect near zero magnetic field

A. J. Bestwick, E. J. Fox, Xufeng Kou, Lei Pan, Kang L. Wang, D. Goldhaber-Gordon

Research output: Contribution to journalArticlepeer-review

159 Citations (Scopus)

Abstract

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 10000 and a longitudinal resistivity under 1Ω 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.

Original languageEnglish
Article number187201
JournalPhysical review letters
Volume114
Issue number18
DOIs
Publication statusPublished - 2015 May 4

All Science Journal Classification (ASJC) codes

  • Physics and Astronomy(all)

Fingerprint

Dive into the research topics of 'Precise quantization of the anomalous hall effect near zero magnetic field'. Together they form a unique fingerprint.

Cite this