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arXiv · 1212.2009

Interband Quasiparticle Scattering in Superconducting LiFeAs Reconciles Photoemission and Tunneling Measurements

Christian Hess·Steffen Sykora·Torben Hänke·Ronny Schlegel·Danny Baumann·Volodymyr B. Zabolotnyy·Luminita Harnagea·Sabine Wurmehl·Jeroen van den Brink·Bernd Büchner
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Abstract

Several angle resolved photoemission spectroscopy (ARPES) studies reveal a poorly nested Fermi surface of LiFeAs, far away from a spin density wave instability, and clear-cut superconducting gap anisotropies. On the other hand a very different, more nested Fermi surface and dissimilar gap anisotropies have been obtained from quasiparticle interference (QPI) data, which were interpreted as arising from intraband scattering within hole-like bands. Here we show that this ARPES-QPI paradox is completely resolved by interband scattering between the hole-like bands. The resolution follows from an excellent agreement between experimental quasiparticle scattering data and T-matrix QPI calculations (based on experimental band structure data), which allows disentangling interband and intraband scattering processes.

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Christian Hess, Steffen Sykora, Torben Hänke, Ronny Schlegel, Danny Baumann, Volodymyr B. Zabolotnyy, Luminita Harnagea, Sabine Wurmehl, Jeroen van den Brink, Bernd Büchner. 2013-01-07. Interband Quasiparticle Scattering in Superconducting LiFeAs Reconciles Photoemission and Tunneling Measurements. https://doi.org/10.1103/physrevlett.110.017006

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