From Fe-based Superconductors to Topological Materials

Abstract:

More than one decade the material class of Fe-based superconductors has provided a fruitful platform for the investigation of the interplay between charge, spin and orbital degrees of freedom. Electronic properties governed by the Fe 3d states manifest themselves in a rich electronic phase diagram and electronic correlations, which are tunable across the different Fe-pnictide and Fe-chalcogenide compounds. Latter have attracted wide attention with high-temperature superconductivity in 1 uc FeSe/SrTiO3 platforms as well as with predictions of topological phases (band inversions) in FeSe and FeSe1-xTex. Topological materials can be classified by symmetries, and due to an intensified research,many different compounds (semiconductors, complex oxides, iridates, 2D layered structures, etc.) and hybrid structures with large spin-orbit coupling were identified for showing topologically protected surface (edge) states and realizing Dirac (Weyl)-like dispersions as well as Berry phase physics in condensed matter. Displayed anomalous electrical transport and magnetic properties include an anomalous metal behavior in superconductor-to-insulator transitions due to potential bosonic topological insulators in 2D electronic systems, unconventional and topological superconductivity, localization effects, quantum anomalous Hall effect or Nernst effect, etc. Interesting questions address the role of disorder, transitions between different (topological) phases and the electrical response upon the irradiation with light.In my talk I will cover selected previous work on Fe-based superconductors and point out possible future topics on topological and complex materials that contribute to ct.qmatcenter activities.

Where: Zoom Meeting:

https://tu-dresden.zoom.us/j/85193786651?pwd=Q0V0KzR2emsyRnhvdzdLRDdTSnBaZz09
Meeting ID: 851 9378 6651
Passcode: reG3NboG#N