Hubertus Luetkens

TL;DR: In this paper, the structural and electronic phase diagram is investigated by means of X-ray scattering, muon spin relaxation and Mossbauer spectroscopy on the series LaO(1-x)F(x)FeAs.

TL;DR: The synthesis of large single crystals of a new FeSe layer superconductor Cs( 0.8)(FeSe(0.98))(2) is reported on, which shows a slightly lower superconducting transition temperature and the T(c) dependence on the anion height was found to be analogous to those reported for As-containing Fe superconductors and Fe(Se(1 - x)Ch(x)), where Ch = Te, S.

TL;DR: These experiments prove a commensurate static magnetic order with a strongly reduced ordered moment of 0.25(5)muB at the iron site below T(N)=138 K, well separated from a structural phase transition at T(S)=156 K.

TL;DR: A detailed investigation of the electronic phase diagram of FeSe1-x under pressures up to 1.4 GPa by means of ac magnetization and muon-spin rotation finds it to be one of the most interesting superconducting systems investigated extensively at present.

TL;DR: It is demonstrated that it is possible to alter the electronic states of non-ferromagnetic materials, such as diamagnetic copper and paramagnetic manganese, to overcome the Stoner criterion and make them ferromagnetic at room temperature.