Quantum mold casting for topological insulating and edge states

TL;DR

This paper proposes a method to dynamically create stable topological insulators using non-Hermitian unidirectional hopping and periodic driving, demonstrated through numerical models, revealing a classical analogy of quantum quench dynamics.

Contribution

It introduces a novel approach to engineer topological quantum states via non-Hermitian dynamics and periodic driving, expanding the toolkit for topological matter manipulation.

Findings

Successful numerical demonstration with QWZ model and SSH chain.

Approximate realization of stable topological insulators through unidirectional dynamical processes.

Revealed classical analogy of quench dynamics in quantum topological systems.

Abstract

We study the possibility of transferring fermions from a trivial system as particle source to an empty system but at topological phase as a mold for casting a stable topological insulator dynamically. We show that this can be realized by a non-Hermitian unidirectional hopping, which connects a central system at topological phase and a trivial flat-band system with a periodic driving chemical potential, which scans over the valence band of the central system. The near exceptional-point dynamics allows a unidirectional dynamical process: the time evolution from an initial state with full-filled source system to a stable topological insulating state approximately. The result is demonstrated numerically by a source-assistant QWZ model and SSH chain in the presence of random perturbation. Our finding reveals a classical analogy of quench dynamics in quantum matter and provides a way for topological quantum state engineering.