The quantum anomalous Hall effect in magnetic topological insulators has potential for use in quantum resistance metrology applications. Electronic conductance is quantized to e²/h (where e is the elementary charge and h is the Planck constant) due to the effect, which persists down to zero external magnetic field and is compatible with the quantum standard of voltage. However, metrological applications of the quantum anomalous Hall effect are currently restricted by the need for low measurement currents and low temperatures. Here we report 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, we simultaneously inject current into two disconnected perimeters of a multi-terminal Corbino device, which is based on V_0.1(Bi_0.2Sb_0.8)_1.9Te₃, to balance the electrochemical potential between the edges. This screens the electric field that drives backscattering through the bulk and thus improves the stability of the quantization at increased currents. Our approach could also be applied to existing quantum resistance standards that rely on the integer quantum Hall effect.

磁拓扑绝缘体中的量子反常霍尔效应具有在量子电阻计量应用中的应用潜力。由于该效应，电子电导被量子化为e ² / h（其中e是基本电荷，h是普朗克常数），该效应持续到零外部磁场，并且与电压的量子标准兼容。然而，量子反常霍尔效应的计量应用目前受到低测量电流和低温需求的限制。在这里，我们报告了一种测量方案，该方案提高了零磁场量子反常霍尔电阻的鲁棒性，并将其工作范围扩展到更高的电流。在该方案中，我们同时将电流注入基于V _0.1 (Bi _0.2 Sb _0.8 ) _1.9 Te ₃的多端子Corbino器件的两个断开的周边，以平衡边缘之间的电化学电势。这屏蔽了驱动反向散射穿过体的电场，从而提高了电流增加时的量化稳定性。我们的方法也可以应用于依赖整数量子霍尔效应的现有量子电阻标准。