Aharonov-Bohm effect in helical systems

Helical states are a special state of matter with a lock-in relation between momentum and spin of electrons or quasi particle excitations. It has recently been shown, that many body effects can lead to the formation of helical edge states in one dimensional quantum wires. This results in highly interesting transport properties, like the ideal transport of charge and spin, for future electronic devices [1–5]. However, there is no direct experimental evidence confirming the helical transport in 1D. Therefore, it is highly important to develop new theoretical suggestions, which could help to find smoking gun evidence of helical states in 1D wires. In this work we have investigated the Aharonov-Bohm (AB) effect in helical systems as a tool to detect the helical nature in 1D wires. We have considered two possible setups, a helical ABring connected to helical leads and a helical AB-ring connected to metallic non-helical leads, and have shown, that the latter setup yields oscillations under certain conditions, whereas they are absent in the full helical setup. We believe our results can be used as a hint to develop reliable tools and thus proof helical transport in 1D quantum wires.