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arXiv · 1504.06347

Momentum dependence of the superconducting gap and in-gap states in MgB2 multi-band superconductor

Daixiang Mou·Rui Jiang·Valentin Taufour·S. L. Bud'ko·P. C. Canfield·Adam Kaminski
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Abstract

We use tunable laser based Angle Resolved Photoemission Spectroscopy to study the electronic structure of the multi-band superconductor, MgB2. These results form the base line for detailed studies of superconductivity in multi-band systems. We find that the magnitude of the superconducting gap on both sigma bands follows a BCS-like variation with temperature with Delta0 ~7 meV. The value of the gap is isotropic within experimental uncertainty and in agreement with pure a s-wave pairing symmetry. We also observe in-gap states confined to kF of the sigma band that occur at some locations of the sample surface. The energy of this excitation, ~3 meV, is inconsistent with scattering from the pi band.

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Daixiang Mou, Rui Jiang, Valentin Taufour, S. L. Bud'ko, P. C. Canfield, Adam Kaminski. 2015-04-23. Momentum dependence of the superconducting gap and in-gap states in MgB2 multi-band superconductor. https://arxiv.org/abs/1504.06347

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