Nanowerk April 15, 2024
Metrological applications of the quantum anomalous Hall effect are currently restricted by the need for low measurement currents and low temperatures. Researchers in Germany developed a measurement scheme that increases the robustness of a zero-magnetic-field quantum anomalous Hall resistor and extends its operating range to higher currents. In the scheme, they simultaneously injected current into two disconnected perimeters of a multi-terminal Corbino device to balance the electrochemical potential between the edges. This screened the electric field that drove backscattering through the bulk and thus improved the stability of the quantization at increased currents. According to the researchers their approach could also be applied to existing quantum resistance standards that rely on the integer quantum Hall effect… read more. Open Access TECHNICAL ARTICLE
Electrochemical potential balancing at various temperatures. Credit: Nature Electronics, April 15, 2024