Quantum anomalous Hall effect with a permanent magnet defines a quantum resistance standard
Quantum anomalous Hall effect with a permanent magnet defines a quantum resistance standard
复制标题
DOI：
10.1038/s41567-021-01424-8
复制
发表时间：
2021-12
期刊：
影响因子：
19.6
通讯作者：
Y. Okazaki;T. Oe;M. Kawamura;R. Yoshimi;Shuji Nakamura;S. Takada;M. Mogi;Kei S. Takahashi;A. Tsukazaki;M. Kawasaki;Y. Tokura;N. Kaneko
中科院分区：
文献类型：
--
作者：
Y. Okazaki;T. Oe;M. Kawamura;R. Yoshimi;Shuji Nakamura;S. Takada;M. Mogi;Kei S. Takahashi;A. Tsukazaki;M. Kawasaki;Y. Tokura;N. Kaneko
量子反常霍尔效应 (QAHE), , , , – 是一种输运现象，其中由于铁磁材料即使在零磁场下也会自发磁化，霍尔电阻也会量子化为 von Klitzing 常数。与强磁场下的量子霍尔效应（QHE）类似，QAHE 的量子化霍尔电阻应该是通用的，与实验实现中的细节无关。然而，迄今为止报道的 QAHE 的量化精度比 QHE 差很多。在这里，我们展示了 QAHE 中霍尔电阻量化的精度为十亿分之十。通过直接比较QAHE和QHE，我们确认QAHE的量化精度满足作为电阻主要标准所需的水平。我们通过使用永盘磁体提供的弱磁场来对齐磁化域来实现这种高精度的量化。我们的研究结果为开发无强磁场的量子电阻标准奠定了里程碑。
The quantum anomalous Hall effect (QAHE), , , , –is a transport phenomenon where the Hall resistance is quantized to the von Klitzing constant due to the spontaneous magnetization of a ferromagnetic material even at zero magnetic field. Similar to the quantum Hall effect (QHE) under strong magnetic fields, the quantized Hall resistance of QAHE is supposed to be universal, independent of the details in the experimental realization,. However, the quantization accuracy of QAHE reported so far, –is much poorer than that of QHE. Here we demonstrate a precision of 10 parts per billion of Hall resistance quantization in QAHE. By directly comparing QAHE with QHE, we confirm that the quantization accuracy of QAHE satisfies the required level as a primary standard of electric resistance. We achieve this high accuracy of quantization by using a weak magnetic field supplied by a permanent disc magnet to align the magnetization domains. Our findings establish a milestone for developing a quantum resistance standard without strong magnetic fields.