Asymmetric Transport in Long-Range Interacting Chiral Spin Chains

TL;DR

This paper investigates asymmetric spin transport in long-range chiral spin chains, revealing how interaction range and Dzyaloshinskii-Moriya coupling influence quantum state transfer and entanglement growth, with potential applications in quantum information.

Contribution

It introduces a model combining long-range interactions and chiral effects to control quantum state directionality, supported by numerical and analytical analysis.

Findings

Asymmetric spin excitations depend on interaction range and DM coupling.

Entanglement entropy growth is significantly reduced in these systems.

The model's predictions are testable with current trapped-ion experiments.

Abstract

Harnessing power-law interactions ($1/r^\alpha$) in a large variety of physical systems are increasing. We study the dynamics of chiral spin chains as a possible multi-directional quantum channel. This arises from the nonlinear character of the dispersion with complex quantum interference effects. Using complementary numerical and analytical techniques, we propose a model to guide quantum states to a desired direction. We illustrate our approach using the long-range XXZ model modulated by Dzyaloshinskii-Moriya (DM) interaction. By exploring non-equilibrium dynamics after a local quantum quench, we identify the interplay of interaction range $\alpha$ and Dzyaloshinskii-Moriya coupling giving rise to an appreciable asymmetric spin excitations transport. This could be interesting for quantum information protocols to transfer quantum states, and it may be testable with current trapped-ion experiments. We further explore the growth of block entanglement entropy in these systems, and an order of magnitude reduction is distinguished.