Pair density wave and reentrant superconducting tendencies originating from valley polarization
Pair density wave and reentrant superconducting tendencies originating from valley polarization
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DOI：
10.1103/physrevb.105.l100509
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发表时间：
2021-12
影响因子：
3.7
通讯作者：
Zhaoyu Han;S. Kivelson
中科院分区：
文献类型：
--
作者：
Zhaoyu Han;S. Kivelson
我们研究了具有谷自由度和自旋自由度的二维电子流体的超导配对倾向，无论是在没有还是存在面内磁场的情况下。我们提出了暗示性的理论论点，自发谷极化可以导致奇异的单线态超导倾向，包括在零场的对密度波序和在高场的重入超导。我们还发现极化谷中的磁响应降低，这允许对泡利极限的有限违反。这些结果是用平均场方法对三角格点上的广义t-J模型在稀极限下得到的。最近魔角扭曲的三层石墨烯实验的结果的现象学的相似性。
We investigate superconducting pairing tendencies of a two-dimensional electron fluid with both valley and spin degrees of freedom, both without and in the presence of an in-plane magnetic field. We present suggestive theoretical arguments that spontaneous valley polarization can lead to exotic singlet superconducting tendencies, including pair-density-wave order at zero field and reentrant superconductivity at high field. We also find a reduced magnetic response in the polarized valley, which allows a finite violation of the Pauli limit. These results are obtained by a mean-field approach to a generalized t - J model on a triangular lattice and in the dilute limit. Phenomenological similarities to results of recent magic-angle twisted trilayer graphene experiments are noted.