Networks of quantum nanorings: programmable spintronic devices

TL;DR

This paper demonstrates that small networks of quantum nanorings with tunable spin-orbit interaction can function as programmable spintronic devices, capable of directing electron currents and creating spin-entangled states.

Contribution

It introduces a method to control electron spin states and pathways in quantum ring networks via external gate voltages, enabling programmable spintronic functionalities.

Findings

Small quantum ring networks can direct current to any output port.

Tuning SOI strengths can produce Stern-Gerlach-like spin separation.

Networks exhibit spatial-spin entanglement with adjustable parameters.

Abstract

An array of quantum rings with local (ring by ring) modulation of the spin orbit interaction (SOI) can lead to novel effects in spin state transformation of electrons. It is shown that already small (3x3, 5x5) networks are remarkably versatile from this point of view: Working in a given network geometry, the input current can be directed to any of the output ports, simply by changing the SOI strengths by external gate voltages. Additionally, the same network with different SOI strengths can be completely analogous to the Stern-Gerlach device, exhibiting spatial-spin entanglement.