Edge Properties and Majorana Fermions in the Proposed Chiral d-Wave Superconducting State of Doped Graphene
2012 (English)In: Physical Review Letters, ISSN 0031-9007, Vol. 109, no 19, 197001- p.Article in journal (Refereed) Published
We investigate the effect of edges on the intrinsic d-wave superconducting state in graphene doped close to the van Hove singularity. While the bulk is in a chiral d(x2-y2) + id(xy) state, the order parameter at any edge is enhanced and has d(x2-y2)-symmetry, with a decay length strongly increasing with weakening superconductivity. No graphene edge is pair breaking for the d(x2-y2) state, and there are no localized zero-energy edge states. We find two chiral edge modes which carry a spontaneous, but not quantized, quasiparticle current related to the zero-energy momentum. Moreover, for realistic values of the Rashba spin-orbit coupling, a Majorana fermion appears at the edge when tuning a Zeeman field.
Place, publisher, year, edition, pages
2012. Vol. 109, no 19, 197001- p.
IdentifiersURN: urn:nbn:se:uu:diva-188422DOI: 10.1103/PhysRevLett.109.197001ISI: 000310852000022OAI: oai:DiVA.org:uu-188422DiVA: diva2:577945