在UTe2中观察奇偶平价超导
Zixuan Li1, Camilla M Moir2, Nathan J McKee1
1Department of Physics, Materials Research Institute, The Pennsylvania State University, University Park, PA 16802.
概括
研究人员使用约瑟夫森效应测量结果揭示了UTe2是一种自旋三连体超导体. 这一发现为其奇偶平价配对状态提供了有力的证据,这是这种奇异材料的关键特征.
科学领域:
- 凝聚物质物理学 凝聚物质物理学
- 超导性研究 超导性研究
- 材料科学 材料科学 材料科学
背景情况:
- 超导顺序参数对称性对于理解材料特性至关重要.
- UTe2 呈现出高的上临界场和反入行为,这表明了旋转三元组对配.
- 实验证实UTe2中自旋三重体对称性的证实,特别是在低电场下,仍然难以捉摸.
研究的目的:
- 在UTe2.2中实验确定超导顺序参数的轨道对称性.
- 为UTe2超导的自旋三重性提供相位敏感的证据.
- 调查UTe2.2中安德里耶夫表面结合状态的存在.
主要方法:
- 利用约瑟夫森效应进行相位敏感测量.
- 在s波超导体 (Indium) 和UTe2.2之间采用取决于方向的约瑟夫森合.
- 表面敏感探测器检测安德里耶夫结合状态.
主要成果:
- 约瑟夫森合的方向依赖强烈表明UTe2在接近零磁场的奇偶平价B1u配对状态.
- 这一发现提供了强有力的证据,证明UTe2是一种自旋三元超导体.
- 在 (1-10) 表面上观察到Andreev表面束状态的明显形成.
结论:
- 在低磁场下,UTe2表现出一个奇偶平价,旋转三重体超导状态,特别是B1u对称性.
- 约瑟夫森效应测量为这种配对对称性提供了第一个明确的,相位敏感的证据.
- 对安德里耶夫表面束状态的观察为UTe2超导的非传统性质提供了进一步的见解.
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