Binary topological logic gates in Kane-Mele nanostructures via local control of edge-state transport

TL;DR

This paper demonstrates the feasibility of implementing binary logic gates, specifically NOT and AND, in Kane-Mele nanostructures by controlling edge-state transport through local perturbations.

Contribution

It introduces a simple, physically transparent approach to realize topological binary logic using local electrostatic and magnetic controls in Kane-Mele nanostructures.

Findings

Successfully demonstrated NOT and AND gates in Kane-Mele nanostructures.

Operation relies on rerouting edge currents, not interference.

Gates show robustness within specific parameter ranges.

Abstract

Topological edge states are an attractive starting point for post-CMOS device concepts, but turning them into elementary logic still requires simple architectures with a clear physical mechanism. Here we investigate binary logic in Kane-Mele nanostructures with spatially localized control regions. Logical inputs are encoded through local electrostatic, exchange-like, and Rashba-type perturbations, while the output is read out from terminal transmission within a coherent Landauer-B\"uttiker framework. We demonstrate working NOT and AND gates in multiterminal honeycomb geometries and show, with the help of current maps, that their operation is governed by controlled rerouting of edge currents rather than by fine-tuned interference. Robustness tests further indicate a stable operating window within the tested parameter range for the NOT gate and a somewhat narrower but still reliable one for the AND gate. These results identify Kane-Mele nanostructures as a transparent platform for primitive topological binary logic.