论文标题
在扭曲的双层石墨烯中，具有预先形成对的非常规超导性
Unconventional superconductivity with preformed pairs in twisted bilayer graphene
论文作者
论文摘要
我们提出了魔法扭曲的双层石墨烯中超导性的理论，并在存在磁场的情况下分析了超导相图。也就是说，我们考虑了一个固定状态的颗粒阵列的模型，该模型通过元素间区域的Decalized Fermions杂交。当相互作用导致与谷物内部预先形成的库珀对的不一致状态时，我们研究了强烈的耦合情况。不同谷物之间的安德里夫散射通过较低温度下的全球相相连接状态表现出来。我们证明，预先形成的库珀配对状态与larkin-ovchinnikov-fulde-ferrell状态之间的新相变可能是由面内磁场的自旋成对效应引起的。在强耦合案例中，表现出上临界磁场的增强。
We present a theory of superconductivity in magic-angle twisted bilayer graphene and analyze the superconducting phase diagram in presence of the magnetic field. Namely, we consider a model of a granular array hosting localized states, which are hybridized via the delocalized fermions in the inter-grain regions. We study a strong coupling situation when the interactions lead to an incoherent state with preformed Cooper pairs inside the grains. The Andreev scattering among different grains manifests itself through the global phase-coherent superconducting state at lower temperatures. We demonstrate that a new phase transition between the preformed Cooper pairing state and the Larkin-Ovchinnikov-Fulde-Ferrell state might be induced by the spin pair-breaking effect of in-plane magnetic field. The upper critical magnetic field is shown to be enhanced in the strong coupling case.
