Topological pair-density-wave superconducting states.
Topological pair-density-wave superconducting states.
复制标题
拓扑对密度波超导态。
DOI：
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发表时间：
2014
影响因子：
8.6
通讯作者：
E. Fradkin
中科院分区：
文献类型：
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作者：
G. Cho;R. Soto;E. Fradkin
我们证明了扩展海森堡-哈伯德模型中出现的对密度波（PDW）超导态在存在Ising自旋对称的情况下是拓扑的，并且在开放边界和均匀d波一维超导体的交界处支持马约拉纳零模式（MZM）。与传统的有限动量对态类似，PDW态的序参量是一个有限动量的电荷-2e场。然而，这里的序参量是一个四次电子算符，传统的平均场理论不能用于研究这种状态。我们用玻色子化证明了一维PDW态在边界处有一个MZM。这种超导态是一种奇异的拓扑相，支持马约拉纳费米子具有有限动量配对场和电荷-4e超导性。
We show that the pair-density-wave (PDW) superconducting state emergent in extended Heisenberg-Hubbard models in two-leg ladders is topological in the presence of an Ising spin symmetry and supports a Majorana zero mode (MZM) at an open boundary and at a junction with a uniform d-wave one-dimensional superconductor. Similarly to a conventional finite-momentum paired state, the order parameter of the PDW state is a charge-2e field with finite momentum. However, the order parameter here is a quartic electron operator and conventional mean-field theory cannot be applied to study this state. We use bosonization to show that the 1D PDW state has a MZM at a boundary. This superconducting state is an exotic topological phase supporting Majorana fermions with finite-momentum pairing fields and charge-4e superconductivity.