Enhanced Majorana stability in a three-site Kitaev chain
Majorana zero modes are non-Abelian quasiparticles predicted to emerge at the edges of topological superconductors. A one-dimensional topological superconductor can be realized with the Kitaev model-a chain of spinless fermions coupled via p-wave superconductivity and electron hopping-which becomes topological in the long-chain limit. Here we realize a three-site Kitaev chain using semiconducting quantum dots coupled by superconducting segments in a hybrid InSb/Al nanowire. We investigate the robustness of Majorana zero modes under varying coupling strengths and electrochemical potentials, comparing two- and three-site chains realized within the same device. We observe that extending the chain to three sites enhances the stability of the zero-energy modes, especially against variations in the coupling strengths. This experiment lacks superconducting phase control, yet numerical conductance simulations with phase averaging align well with our observations. Our results demonstrate the scalability of quantum-dot-based Kitaev chains and its benefits for Majorana stability.
Authors
- Francesco Zatelli (ORCID: https://orcid.org/0000-0002-4250-6566)
- Michael Wimmer (ORCID: https://orcid.org/0000-0001-6654-2310)
- Thomas Van Caekenberghe (ORCID: https://orcid.org/0000-0002-4278-0952)
- Alberto Bordin (ORCID: https://orcid.org/0000-0003-0632-747X)
- Erik P. A. M. Bakkers (ORCID: https://orcid.org/0000-0002-8264-6862)
- Jan Cornelis Wolff
- David van Driel (ORCID: https://orcid.org/0009-0002-6429-9358)
- Saša Gazibegović (ORCID: https://orcid.org/0000-0002-2740-9688)
- Tom Dvir (ORCID: https://orcid.org/0000-0003-0966-2564)
- Leo P. Kouwenhoven (ORCID: https://orcid.org/0000-0002-7046-8181)
- Ghada Badawy (ORCID: https://orcid.org/0000-0001-9933-3435)
- Grzegorz P. Mazur (ORCID: https://orcid.org/0000-0002-7611-8115)
- Sebastiaan L. D. ten Haaf (ORCID: https://orcid.org/0009-0004-3997-474X)
- Nick van Loo (ORCID: https://orcid.org/0000-0001-7461-5428)
- Chun-Xiao Liu (ORCID: https://orcid.org/0000-0002-4071-9058)
- Yining Zhang (ORCID: https://orcid.org/0000-0003-0128-1863)
- Guanzhong Wang (ORCID: https://orcid.org/0000-0002-3260-3055)
Institutions
- University of Oxford (GB)
- QuTech (NL)
- Eindhoven University of Technology (NL)
- Delft University of Technology (NL)
Publication Details
- Journal
- Nature Nanotechnology
- Published
- 2025-03-31
- DOI
- https://doi.org/10.1038/s41565-025-01894-4
- Citations
- 25
- Primary Topic
- Topological Materials and Phenomena
- Type
- article
- Field-Weighted Citation Impact
- 31.17
Funders
- Microsoft
- Nederlandse Organisatie voor Wetenschappelijk Onderzoek