Unpaired Majorana Modes in Josephson-Junction Arrays with Gapless Bulk Excitations.

Phys Rev Lett

Department of Physics and Astronomy, Rutgers The State University of New Jersey, 136 Frelinghuysen road, Piscataway, New Jersey 08854, USA.

Published: November 2015

The search for Majorana bound states in solid-state physics has been limited to materials that display a gap in their bulk spectrum. We show that such unpaired states appear in certain quasi-one-dimensional Josephson-junction arrays with gapless bulk excitations. The bulk modes mediate a coupling between Majorana bound states via the Ruderman-Kittel-Yosida-Kasuya mechanism. As a consequence, the lowest energy doublet acquires a finite energy difference. For a realistic set of parameters this energy splitting remains much smaller than the energy of the bulk eigenstates even for short chains of length L∼10.

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http://dx.doi.org/10.1103/PhysRevLett.115.197001DOI Listing

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