Regensburg 2013 – scientific programme
Parts | Days | Selection | Search | Updates | Downloads | Help
TT: Fachverband Tiefe Temperaturen
TT 36: Superconductivity: Fe-based Superconductors - Fe(Se,Te), LiFeAs, and other Materials
TT 36.1: Talk
Wednesday, March 13, 2013, 09:30–09:45, H18
Interplay between lattice and spin degrees of freedom in FeSe superconductors — Vladimir Gnezdilov1, •Peter Lemmens2, Yurii Pashkevich3, Tatiana Shevtsova3, Alexander Gusev3, Dirk Wulferding2, Dmitriy Chareev4, and Alexander Vasiliev5 — 1ILTPE, Kharkov, Ukraine — 2IPKM, TU-BS, Braunschweig — 3DonFTI, Donetsk, Ukraine — 4IEM, RAS, Moscow, Russia — 5Moscow State Univ., Moscow, Russia
Recently grown high quality FeSe single crystals show pronounced anomalies in the temperature dependent Raman spectra. An anomalous hardening of one phonon mode upon decreasing temperature is related to local fluctuations of the Fe orbital occupation, described by the Fe spin state. The enhancement of the low-frequency spectral weight above the structural phase transition temperature TS and its change below TS is discussed in connection with the opening of a spin state gap which results in the absence of magnetic order in FeSe. Work supported by DFG, B-IGSM and NTH School for Contacts in Nanosystems.