Spin-selective Aharonov-Casher caging in a topological quantum network

TL;DR

This paper demonstrates that a topological quantum network exhibits spin-selective localization due to the Aharonov-Casher phase, with exact results showing extreme caging for specific half-integer spins under certain conditions.

Contribution

It introduces a novel spin-selective caging mechanism in a topological quantum network induced by the Aharonov-Casher phase, with exact analytical results.

Findings

Spin-selective extreme localization occurs at specific spin and electric field conditions.

Half-integer spins undergo complete caging, integer spins are spared.

Experimental parallels are drawn with photonic lattice systems.

Abstract

A periodic network of connected rhombii, mimicking a spintronic device, is shown to exhibit an intriguing spin selective extreme localization, when submerged in a uniform out of plane electric field. The topological Aharonov Casher phase acquired by a travelling spin is seen to induce a complete caging, triggered at a special strength of the spin orbit coupling, for half odd integer spins s \ge n\hbar/2, with n odd, sparing the integer spins. The observation finds exciting experimental parallels in recent literature on caged, extreme localized modes in analogous photonic lattices. Our results are exact.