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Part-per-million quantization and current-induced breakdown of the quantum anomalous Hall effect



Eli J. Fox, Ilan T. Rosen, Yanfei Yang, George R. Jones Jr., Randolph Elmquist, Xufeng Kou, Lei Pan, Kang L. Wang, D. Goldhaber-Gordon


In the quantum anomalous Hall effect, quantized Hall resistance and vanishing longitudinal resistivity are predicted to result from the presence of dissipationless, chiral edge states and an insulating two-dimensional bulk, without requiring an external magnetic field. Here, we explore the potential of this effect in magnetic topological insulator thin films for metrological applications. Using a cryogenic current comparator system, we measure quantization of the Hall resistance to within one part per million and, at lower current bias, longitudinal resistivity under 10 mΩ at zero magnetic field. Increasing the current density past a critical value leads to a breakdown of the quantized, low-dissipation state, which we attribute to electron heating in bulk current flow. We further investigate the pre-breakdown regime by measuring transport dependence on temperature, current, and geometry, and find evidence for bulk dissipation, including thermal activation and possible variable-range hopping.
Physical Review B


Fox, E. , Rosen, I. , Yang, Y. , Jones Jr., G. , Elmquist, R. , Kou, X. , Pan, L. , Wang, K. and Goldhaber-Gordon, D. (2018), Part-per-million quantization and current-induced breakdown of the quantum anomalous Hall effect, Physical Review B, [online], (Accessed April 19, 2024)
Created August 26, 2018, Updated April 8, 2022