1212.2009 (Christian Hess et al.)

Resolving the quasiparticle scattering paradox in superconducting LiFeAs    [PDF]

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

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.

View original: http://arxiv.org/abs/1212.2009