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arXiv · 1710.04090

Zero-field quantum anomalous Hall metrology as a step towards a universal quantum standard unit system

Martin Goetz·Kajetan M. Fijalkowski·Eckart Pesel·Matthias Hartl·Steffen Schreyeck·Martin Winnerlein·Stefan Grauer·Hansjoerg Scherer·Karl Brunner·Charles Gould·Franz J. Ahlers·Laurens W. Molenkamp
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Abstract

In the quantum anomalous Hall effect, the edge states of a ferromagnetically doped topological insulator exhibit quantized Hall resistance and dissipationless transport at zero magnetic field. Up to now, however, the resistance was experimentally assessed with standard transport measurement techniques which are difficult to trace to the von-Klitzing constant R$_K$ with high precision. Here, we present a metrologically comprehensive measurement, including a full uncertainty budget, of the resistance quantization of V-doped (Bi,Sb)$_2$Te$_3$ devices without external magnetic field. We established as a new upper limit for a potential deviation of the quantized anomalous Hall resistance from RK a value of 0.26 +- 0.22 ppm, the smallest and most precise value reported to date. This provides another major step towards realization of the zero-field quantum resistance standard which in combination with Josephson effect will provide the universal quantum units standard in the future.

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Martin Goetz, Kajetan M. Fijalkowski, Eckart Pesel, Matthias Hartl, Steffen Schreyeck, Martin Winnerlein, Stefan Grauer, Hansjoerg Scherer, Karl Brunner, Charles Gould, Franz J. Ahlers, Laurens W. Molenkamp. 2017-10-11. Zero-field quantum anomalous Hall metrology as a step towards a universal quantum standard unit system. https://doi.org/10.1063/1.5009718

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