在双层T_{d}-MoTe_{2}中具有双重异性极导性
Zizhong Li1, Apoorv Jindal2, Alex Strasser3
1Department of Materials Science and Engineering, <a href="https://ror.org/01y2jtd41">University of Wisconsin-Madison</a>, Madison, Wisconsin 53706, USA.
Physical review letters
|December 6, 2024
概括
少数层的Td-二甲 (MoTe2) 超导体表现出超出保利极限的增强的临界场. 倾斜的Ising旋转轨道合驱动了这种增强,通过对双层MoTe2.2的实验得到证实.
科学领域:
- 凝聚物质物理学 凝聚物质物理学
- 材料科学 材料科学 材料科学
- 超导电性 超导电性 超导电性
背景情况:
- 具有强大的自旋轨道合 (SOC) 的非中心对称2D超导体使得超越保利极限的探索成为可能.
- 少数层的Td-二甲 (MoTe2) 显示上临界场超过了保利极限高达600%.
- 讨论了这种增强的潜在机制,一些理论建议旋转轨道平价合或倾斜的Ising SOC.
研究的目的:
- 为了研究双层Td-MoTe2在平面内磁场下的超导行为.
- 探索磁场角和外平面电场对超导的影响.
- 为了确定二层Td-MoTe2中占主导地位的SOC机制.
主要方法:
- 在双层Td-MoTe2.2中实验测量了超导特性.
- 平面内磁场角度和平面外电场强度的系统变化.
- 实验性SOC强度与第一原则计算的比较.
主要成果:
- 双层MoTe2中的超导性表现出双重对称性,临界场的最大值沿着b轴,最小值沿着a轴.
- 这种双重旋转对称性在超导区域和铁电歇斯底里循环中是稳定的.
- 实验性SOC强度 (高达16.4 meV) 与理论上的旋转纹理和旋转分裂保持一致.
结论:
- 倾斜的Ising旋转轨道合被确定为双层Td-MoTe2.2中控制超导性的主要机制.
- 观察到的双重对称性及其强度为磁力,铁电和超导的相互作用提供了关键的见解.
- 这项研究促进了对2D材料中非传统超导性的理解.
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