Presentation on theme: "BiS 2 compounds: Properties, effective low- energy models and RPA results George Martins (Oakland University) Adriana Moreo (Oak Ridge and Univ. Tennessee)"— Presentation transcript:
BiS 2 compounds: Properties, effective low- energy models and RPA results George Martins (Oakland University) Adriana Moreo (Oak Ridge and Univ. Tennessee) Elbio Dagotto (Oak Ridge and Univ. Tennessee) Supported by DOE through Oak Ridge Nat. Lab. Martins, Moreo, and Dagotto PRB 87, 0811021(R) (2013) International Workshop on Recent Developments in Fe-based HTc Superconductors Long Island 6 th September 2013
BiS 2 –based family of superconductors Basic properties Experimental results (brief summary) Band structure (2-band effective model) Phonons or unconventional? RPA results Fermi surface nesting: Peculiar pairing properties: A 1g and B 2g are degenerate. Much more research is needed.
Obtaining the RPA pairing functions spin charge very pronounced peak at incommensurate k vector singlet pairing interaction projected pairing interaction eigenvalue problem, with matrix indexes k and k’ gap function g α associated to largest eigenvalue will have the highest T c
Conclusions Properties of new BiS 2 -based SC family was presented: Layered material Semiconducting /metallic 2 6p bands minimum model Phonons or unconventional? RPA results show: Magnetic fluctuations dominate Pairing is highly dependent on nesting A1g (no nodes) and B2g (nodal) are degenearte