论文标题
Josephson在I型Weyl半法中的效应
Josephson effect in type-I Weyl Semimetals
论文作者
论文摘要
凝结物质中的紧急韦伊尔葬礼通常会破坏洛伦兹的不变性，从而导致倾斜（I型）或过度倾斜（类型II）能量分散体。倾斜能谱可以在设置的结中导致外来的量子干扰效应。在这里，我们从理论上研究了韦尔超导体 - - - - - - - 韦尔（Semi）金属 - - 韦尔（Metai-Weyl）超导体连接的Josephson电流，该连接是时间反转（TR）损坏的I型Weyl semimetal。我们证明，在反转对称倾斜的情况下，类似BCS的配对的库珀对获得了有限的动量。因此，该系统表现出倾斜诱导异常的当前相位关系，这些相位关系由超急流$ 0 $ - $π$ transition和Josephson $ ϕ $ ninction表现出来。相反，在反转倾斜和Weyl超导体中的FFLO样配对的情况下，这些效果仍然不存在。我们通过研究临界电流对连接长度的依赖性，进一步绘制了两种不同类型的配对类型之间的质量差异。我们的研究开辟了一条新的途径，以探测三折的Weyl半学中非常规超导配对。同样有趣的是，Weyl节点中的倾斜自然会导致该模型中的异常相关关系，而无需进行任何磁性操纵！
The emergent Weyl fermions in condensed matter generally break the Lorentz invariance resulting in a tilted (type-I) or over-tilted (type-II) energy dispersion. The tilting energy spectrums can lead to exotic quantum interference effects in a junction set up. Here, we theoretically investigate the Josephson current in a Weyl superconductor-Weyl (semi)metal-Weyl superconductor junction of a time-reversal (TR) broken type-I Weyl semimetal. We demonstrate that the Cooper pairs of BCS-like pairing acquire a finite momentum in case of inversion symmetric tilt. Consequently, the system exhibits tilt induced anomalous current phase relations which are manifested by supercurrent $0$-$π$ transition and Josephson $ϕ$ junction. On the contrary, these effects remain absent in case of inversion breaking tilt and for FFLO-like pairing in the Weyl superconductor. We further chart out qualitative differences between the two distinct types of pairings by studying the critical current dependency on junction length. Our study opens a new avenue to probe the unconventional superconducting pairings in TR-broken Weyl semimetals. It is also quite interesting that the tilting in Weyl nodes naturally leads to anomalous current phase relations in this model without any magnetic manipulation!
