NMR investigation of superconductivity and antiferromagnetism in CaFe${}_2$As${}_2$ under pressure

We report ${}^{75}$As NMR measurements in CaFe${}_2$As${}_2$, made under applied pressures up to 0.83 GPa produced by a standard clamp pressure cell. Our data reveal phase segregation of paramagnetic (PM) and antiferromagnetic (AFM) phases over a range of pressures, with the AFM phase more than 90 % dominant at low temperatures. In situ RF susceptibility measurements indicate the presence of superconductivity. ${}^{75}$As spin-lattice relaxation experiments indicate that the ${}^{75}$As nuclei sample the superconductivity while in the magnetically-ordered environment.