Magnetic and electronic properties of layered antiferromagnets probed by NMR

点击翻译按钮获取中文摘要

The electronic and magnetic properties of layered antiferromagnetic spin systems will be probed in this project by nuclear magnetic resonance (NMR). Measurements of the NMR spectra, the Knight shift and the nuclear relaxation time T1 and T2 will be employed to investigate three exemplary systems (A): the Berezinskii-Kosterlitz- Thouless (BKT) behavior of BaNi2−xMgxV2O8, (B): the magnetic structure and electrical conductivity of Y2−xCaxBaCuO5, and (C): the magnetism and superconductivity in the iron arsenide system (Ba1−xKx)Fe2As2. The influence of doping with the nonmagnetic atoms Ca, Mg and K on the magnetic correlation length of quasi-two-dimensional antiferromagnets will be analyzed, in order to shed light on the microscopic mechanisms which determine the interplay between quasi 2D antiferromagnetic spin correlation and superconductivity.