Dresden 2017 – wissenschaftliches Programm
TT 53.11: Poster
Mittwoch, 22. März 2017, 15:00–19:00, P2-OG2
Detecting sign-changing superconducting gap in LiFeAs using quasiparticle interference — •Dustin Altenfeld1, Peter J. Hirschfeld2, Igor I. Mazin3, and Ilya Eremin1 — 1Institut für Theoretische Physik III, Ruhr-Universität Bochum, D-44801 Bochum, Germany — 2Department of Physics, University of Florida, Gainesville, Florida 32611, USA — 3Code 6393, Naval Research Laboratory, Washington, DC 20375, USA
We present quasiparticle interference (QPI) measurement in Fe-based superconductors as a robust way of determining the superconducting gap sign structure in experiment. We show that the bias dependence of the signed symmetrized and antisymmetrized QPI maps are useful to obtain a characteristic signature of a gap sign change or lack thereof, starting from two-band model up to ab initio based band structure calculation. The experimental realization of the suggested method was successfully realized in FeSe, where a sign changing gap sign structure was identified. We provide a motivation for the application to the LiFeAs compounds.