Abstract
We investigate the effect of correlated disorder on Majorana zero modes (MZMs) bound to magnetic vortices in two-dimensional topological superconductors. By starting from a lattice model of interacting fermions with a px±ipy superconducting ground state in the disorder-free limit, we use perturbation theory to describe the enhancement of the Majorana localization length at weak disorder and a self-consistent numerical solution to understand the breakdown of the MZMs at strong disorder. We find that correlated disorder has a much stronger effect on the MZMs than uncorrelated disorder and that it is most detrimental if the disorder correlation length ℓ is on the same order as the superconducting coherence length ζ. In contrast, MZMs can survive stronger disorder for ℓ≪ζ as random variations cancel each other within the length scale of ζ, while an MZM may survive up to very strong disorder for ℓ≫ζ if it is located in a favorable domain of the given disorder realization.
Original language | English |
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Article number | L020505 |
Journal | Physical Review B |
Volume | 104 |
Issue number | 2 |
DOIs | |
State | Published - Jul 1 2021 |
Funding
Acknowledgments. We thank Cristian Batista for useful discussions. This research was sponsored by the US Department of Energy, Office of Science, Basic Energy Sciences, Materials Sciences and Engineering Division. Preliminary modeling by G.B.H. was supported by the Laboratory Directed Research and Development Program of Oak Ridge National Laboratory, managed by UT-Battelle, LLC, for the US Department of Energy. C.C. was partially supported by the DOE Science Undergraduate Laboratory Internships (SULI) program. This manuscript has been authored by UT-Battelle, LLC under Contract No. DE-AC05-00OR22725 with the US Department of Energy. The United States Government retains and the publisher, by accepting the article for publication, acknowledges that the United States Government retains a nonexclusive, paid-up, irrevocable, worldwide license to publish or reproduce the published form of this manuscript, or allow others to do so, for United States Government purposes. The Department of Energy will provide public access to these results of federally sponsored research in accordance with the DOE Public Access Plan .
Funders | Funder number |
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DOE Science Undergraduate Laboratory Internships | |
SULI | |
U.S. Department of Energy | |
Office of Science | |
Basic Energy Sciences | |
Oak Ridge National Laboratory | |
Division of Materials Sciences and Engineering |