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arXiv · 2510.20538

Quantifying robustness and locality of Majorana bound states in interacting systems

William Samuelson·Juan Daniel Torres Luna·Sebastian Miles·A. Mert Bozkurt·Martin Leijnse·Michael Wimmer·Viktor Svensson
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Abstract

Protecting qubits from perturbations is a central challenge in quantum computing. Topological superconductors with separated Majorana bound states (MBSs) provide a strong form of protection that only depends on the locality of perturbations. While the link between MBS separation, robust degeneracy, and protected braiding is well understood in non-interacting systems, recent experimental progress in short quantum-dot-based Kitaev chains highlights the need to establish these connections rigorously for interacting systems. We do this by defining MBSs from many-body ground states and show how their locality constrains their coupling to an environment. This, in turn, quantifies the protection of the energy degeneracy and the feasibility of non-abelian braiding.

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William Samuelson, Juan Daniel Torres Luna, Sebastian Miles, A. Mert Bozkurt, Martin Leijnse, Michael Wimmer, Viktor Svensson. 2025-10-23. Quantifying robustness and locality of Majorana bound states in interacting systems. https://doi.org/10.1103/pw51-tnsz

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