Regensburg 2016 – scientific program
O 81.3: Talk
Thursday, March 10, 2016, 11:15–11:30, H4
Simulating atomic-scale phenomena on surfaces of unconventional superconductors — •Andreas Kreisel1, Peayush Choubey2, Tom Berlijn3, Brian Andersen1, and Peter Hirschfeld2 — 1Niels Bohr Institute, Denmark — 2Univ. of Florida, USA — 3CNMS & CSMD, Oak Ridge Nat. Lab., USA
Interest in atomic scale effects in superconductors has increased because of two general developments: First, the discovery of new materials as the cuprate superconductors, heavy fermion and Fe-based superconductors where the coherence length of the cooper pairs is as small to be comparable to the lattice constant, rendering small scale effects important. Second, the experimental ability to image sub-atomic features using scanning-tunneling microscopy which allows to unravel numerous physical properties of the homogeneous system such as the quasi particle excitation spectra or various types of competing order as well as properties of local disorder. On the theoretical side, the available methods are based on lattice models restricting the spatial resolution of such calculations. In the present project we combine lattice calculations using the Bogoliubov-de Gennes equations describing the superconductor with wave function information containing sub-atomic resolution obtained from ab initio approaches. This allows us to calculate phenomena on surfaces of superconductors as directly measured in scanning tunneling experiments and therefore opens the possibility to identify underlying properties of these materials and explain observed features of disorder. It will be shown how this method applies to the cuprate material Bi2Sr2CaCu2O8 and a Fe based superconductor.