论文标题
在非炎热的时间反转对称浮标梯子中控制拓扑传输的方向
Controlling the direction of topological transport in a non-Hermitian time-reversal symmetric Floquet ladder
论文作者
论文摘要
我们提出了一个一维的浮子梯子，该梯子具有两个不同方向性的不同拓扑传输通道。传输通道发生是由于$ \ Mathbb Z_2 $非铁floquet拓扑阶段受到时间反向对称性的保护。该阶段的签名是两对克莱默斯脱位浮标的胶质带，它们被假想的间隙隔开。我们讨论如何在光子波导晶格中实现浮梯，并表明可以通过将两个光束聚焦到相邻的波导指导中，从而在所得波导结构中的传输方向进行外部控制。两条光束之间的相对相位选择两个传输通道中的哪一个主要是人口组成的，而两个光束的入射角则确定了哪些传输通道被非弱者损失抑制。我们确定了运输外部控制的最佳晶格参数，并证明了这种机制对疾病的鲁棒性。
We propose a one-dimensional Floquet ladder that possesses two distinct topological transport channels with opposite directionality. The transport channels occur due to a $\mathbb Z_2$ non-Hermitian Floquet topological phase that is protected by time-reversal symmetry. The signatures of this phase are two pairs of Kramers degenerate Floquet quasienergy bands that are separated by an imaginary gap. We discuss how the Floquet ladder can be implemented in a photonic waveguide lattice and show that the direction of transport in the resulting waveguide structure can be externally controlled by focusing two light beams into adjacent waveguides. The relative phase between the two light beams selects which of the two transport channels is predominantly populated, while the angles of incidence of the two light beams determine which of the transport channels is suppressed by non-Hermitian losses. We identify the optimal lattice parameters for the external control of transport and demonstrate the robustness of this mechanism against disorder.
