Campus Units

Physics and Astronomy, Ames Laboratory

Document Type

Article

Publication Version

Published Version

Publication Date

6-1-2015

Journal or Book Title

Physical Review B

Volume

91

Issue

21

First Page

214519

DOI

10.1103/PhysRevB.91.214519

Abstract

We use tunable laser-based angle-resolved photoemission spectroscopy to study the electronic structure of the multiband superconductor MgB2. These results form the baseline for detailed studies of superconductivity in multiband systems. We find that the magnitude of the superconducting gap on both σ bands follows a BCS-like variation with temperature with Δ0∼7meV. The value of the gap is isotropic within experimental uncertainty and in agreement with a pure s-wave pairing symmetry. We also observe in-gap states confined to kF of the σ band that occur at some locations of the sample surface. The energy of this excitation, ∼3 meV, is somewhat larger than the previously reported gap on π Fermi sheet and therefore we cannot exclude the possibility of interband scattering as its origin.

Comments

This article is published as Mou, Daixiang, Rui Jiang, Valentin Taufour, S. L. Bud'ko, P. C. Canfield, and Adam Kaminski. "Momentum dependence of the superconducting gap and in-gap states in MgB 2 multiband superconductor." Physical Review B 91, no. 21 (2015): 214519. DOI: 10.1103/PhysRevB.91.214519. Posted with permission.

Copyright Owner

American Physical Society

Language

en

File Format

application/pdf

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