Relation between superconductivity and tetragonal phase stabilized by uniaxial pressure in CaFe2As2

Abstract

We report on neutron diffraction experiments on high quality CaFe2As2 single crystals performed under uniaxial pressure and combined with in-situ electrical resistance measurements. We conclude that the superconductivity is associated with the high-temperature tetragonal phase that is stabilized down to the lowest temperatures by a small uniaxial pressure of at least 0.075 GPa applied along the c-axis. © Published under licence by IOP Publishing Ltd.