Effect of Majorana Fermions on Andreev Spectroscopy of Multiband Topological Superconductors

• Authors: A. Silva , M. Araújo , P. Sacramento
• Languages of publication: EN

Abstracts

EN

We introduce a model for a multiband topological superconductor with two orbitals per lattice site, in two spatial dimensions. Concentrating on the Andreev reflection problem, the appropriate wave function matching conditions for an interface with a normal single-band metal were previously derived in the framework of a quantum waveguide theory. This theory retrieves the correct number of Majorana fermion states as predicted by the topological index. We obtain the differential conductance as a function of bias voltage, which displays the contribution of the Majorana fermions. Interface disorder is also considered. By varying band structure parameters, topological transitions can be induced, whereby the number of the Majorana modes varies. We calculate the effect of such transitions on the differential conductance.

Keywords

EN

71.10.Fd; 71.10.Pm; 71.10.Li; 73.20.-r; 74.45.+c; 74.20.Rp; 74.70.-b

Discipline

• 73.20.-r: Electron states at surfaces and interfaces
• 71.10.Li: Excited states and pairing interactions in model systems
• 74.70.-b: Superconducting materials other than cuprates(for cuprates, see 74.72.-h; for superconducting films, see 74.78.-w)
• 71.10.Pm: Fermions in reduced dimensions (anyons, composite fermions, Luttinger liquid, etc.)(for anyon mechanism in superconductors, see 74.20.Mn)
• 71.10.Fd: Lattice fermion models (Hubbard model, etc.)
• 74.45.+c: Proximity effects; Andreev reflection; SN and SNS junctions
• 74.20.Rp: Pairing symmetries (other than s-wave)

• Journal: Acta Physica Polonica A
• Year: 2015
• Volume: 128
• Issue: 2
• Pages: 210-212

Dates

published

2015-08

Contributors

author

A. Silva

• CFIF, Instituto Superior Técnico, Universidade de Lisboa, Av. Rovisco Pais, 1049-001 Lisboa, Portugal

author

M. Araújo

• CFIF, Instituto Superior Técnico, Universidade de Lisboa, Av. Rovisco Pais, 1049-001 Lisboa, Portugal
• Departamento de Física, Universidade de Évora, P-7000-671, Évora, Portugal
• Beijing Computational Science Research Center, Beijing 100089, China

author

P. Sacramento

• CFIF, Instituto Superior Técnico, Universidade de Lisboa, Av. Rovisco Pais, 1049-001 Lisboa, Portugal
• Beijing Computational Science Research Center, Beijing 100089, China

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Identifiers

DOI

10.12693/APhysPolA.128.209