Engineering Topological Nodal Line Semimetals in Rashba Spin-Orbit Coupled Atomic Chains

TL;DR

This paper proposes a method to engineer topological nodal line semimetals in atomic chains by modulating charge potential and Rashba spin-orbit coupling, revealing symmetry-protected topological phases with tunable nodal lines.

Contribution

It introduces a novel approach to realize topological nodal line semimetals in atomic chains through periodic modulation of charge potential and RSOC, highlighting the role of symmetry protection.

Findings

Nodal lines appear for periodicities λ=4n with integer n.

The shape and position of nodal lines depend on the relative amplitude of charge potential and RSOC.

The topological phase is protected by an antiunitary particle-hole symmetry.

Abstract

We study an atomic chain in the presence of modulated charge potential and modulated Rashba spin-orbit coupling (RSOC) of equal period. We show that for commensurate periodicities $\lambda=4 n$ with integer $n$, the three-dimensional synthetic space obtained by sliding the two phases of the charge potential and RSOC features a topological nodal line semimetal protected by an antiunitary particle-hole symmetry. The location and shape of the nodal lines strongly depend on the relative amplitude between the charge potential and RSOC.