Chiral edge states and direct edge-to-edge transport in a bosonic magnetic ladder

Abstract

Three-legged magnetic ladder reproduces the main features of two-dimensional Hofstadter butterfly spectrum and the related Chern insulating phases with typical topological edge states, providing new opportunity to study novel quantum states and chiral physics. Here, we propose an efficient scheme to detect various edge states and realize edge-to-edge transport in a three-legged bosonic magnetic ladder. Under the mean field approximation, the eigenstates, chiral edge-state dynamics, and edge-to-edge transport in the system are studied. The energy spectrum and the eigenstates of the system are presented, and both bulk and edge states are obtained, depending on the energy spectrum of the system. The existence of rich edge states (including symmetric and unsymmetric edge states) provides the evidence for realizing the topological transport in the system. Furthermore, chiral edge-state dynamics is excited by applying a weak linear external force, reproducing the underlying eigenstates dynamically, offering a robust way to detect the edge states of the system. Particularly, direct edge-to-edge transport is observed which can be identified by the observables (spin polarization, spin tensor, and chiral currents). The reversal of chiral currents induces the edge-to-edge transport. The edge-to-edge transport time can be manipulated by adjusting the external force and magnetic field. We provide a robust and efficient atomic transport scheme with potential applications in manipulating topological quantum transport and storing quantum states in the ultracold atomic system.

Keywords

• bosonic three-leg ladder
• quantum phase transition
• edge-to-edge transport
• chiral edge dynamics