Probing the low-temperature limit of the quantum anomalous Hall effect
Probing the low-temperature limit of the quantum anomalous Hall effect
复制标题
探索量子反常霍尔效应的低温极限
DOI：
10.1126/sciadv.aaz3595
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发表时间：
2020-06-01
期刊：
影响因子：
13.6
通讯作者：
Wang, Kang L.
中科院分区：
文献类型：
--
作者：
Pan, Lei;Liu, Xiaoyang;Wang, Kang L.
量子反常霍耳效应发生温度低是弱铁磁性和能带参与小的结果。在磁掺杂拓扑绝缘体中观察到量子反常霍尔效应。然而，到目前为止，完全量子化仅限于低于1 K的温度范围，尽管材料的磁有序温度可以超过100 K。在这里，我们研究的温度限制因素的影响，在铬掺杂（BiSb）2Te3系统使用运输和磁光方法。通过对薄膜厚度和掺杂分布的控制，揭示了当前材料体系中量子反常霍尔效应的低发生温度是弱铁磁性和轻微能带参与的综合结果。我们的研究结果可能为寻找高温量子反常霍尔绝缘体和其他拓扑相关现象提供重要的见解。
The low occurring temperature of quantum anomalous Hall effect is a result of weak ferromagnetism and trivial band involvement. Quantum anomalous Hall effect has been observed in magnetically doped topological insulators. However, full quantization, up until now, is limited within the sub–1 K temperature regime, although the material’s magnetic ordering temperature can go beyond 100 K. Here, we study the temperature limiting factors of the effect in Cr-doped (BiSb)2Te3 systems using both transport and magneto-optical methods. By deliberate control of the thin-film thickness and doping profile, we revealed that the low occurring temperature of quantum anomalous Hall effect in current material system is a combined result of weak ferromagnetism and trivial band involvement. Our findings may provide important insights into the search for high-temperature quantum anomalous Hall insulator and other topologically related phenomena.