Topological Superfluid and Majorana Zero Modes in Synthetic Dimension.
Topological Superfluid and Majorana Zero Modes in Synthetic Dimension.
复制标题
合成维数中的拓扑超流体和马约拉纳零模态
DOI：
10.1038/srep15927
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发表时间：
2015-10-30
影响因子：
4.6
通讯作者：
Wang Z
中科院分区：
文献类型：
--
作者：
Yan Z;Wan S;Wang Z
最近的研究表明，一维光学晶格中的多组分自旋轨道耦合费米子可以看作是二维合成晶格中的无自旋费米子，它在合成磁通的作用下运动。在最近的实验中已经观察到这些系统中的量子霍尔边缘态。在本文中，我们研究了吸引哈伯德相互作用的效果。由于Hubbard相互作用在合成维中是长程的，因此它能够有效地在反向传播的手征边缘态之间诱导库珀配对。所得到的一维超流体的拓扑类由二维合成晶格中陈数的奇偶性（偶/奇）决定。我们还表明，在我们的模型中存在的手征对称性，这意味着Z分类和多个零模式的鲁棒性时，这种对称性是不破的。
Recently it has been shown that multicomponent spin-orbit-coupled fermions in one-dimensional optical lattices can be viewed as spinless fermions moving in two-dimensional synthetic lattices with synthetic magnetic flux. The quantum Hall edge states in these systems have been observed in recent experiments. In this paper we study the effect of an attractive Hubbard interaction. Since the Hubbard interaction is long-range in the synthetic dimension, it is able to efficiently induce Cooper pairing between the counterpropagating chiral edge states. The topological class of the resultant one-dimensional superfluid is determined by the parity (even/odd) of the Chern number in the two-dimensional synthetic lattice. We also show the presence of a chiral symmetry in our model, which implies Z classification and the robustness of multiple zero modes when this symmetry is unbroken.