Assessing bound states in a one-dimensional topological superconductor: Majorana versus Tamm

TL;DR

This paper investigates the coexistence and competition of Majorana and Tamm bound states in a one-dimensional topological superconductor, revealing that Tamm states remain localized in gapless regimes and that Majorana polarization indicates a clear transition.

Contribution

It introduces a model analyzing the interplay between Majorana and Tamm bound states, providing analytical and numerical insights into their behavior in topological superconductors.

Findings

Tamm states remain partially localized even in gapless regimes.

Majorana polarization exhibits a clear transition between regimes.

The study highlights the coexistence and competition of different topological bound states.

Abstract

Majorana bound states in topological superconductors have attracted intense research activity in view of applications in topological quantum computation. However, they are not the only example of topological bound states that can occur in such systems. We here study a model in which both Majorana and Tamm bound states compete. We show both numerically and analytically that, surprisingly, the Tamm state remains partially localized even when the spectrum becomes gapless. Despite this fact, we demonstrate that the Majorana polarization shows a clear transition between the two regimes.