Moessbauer and muon spin relaxation investigation of magnetic and superconducting properties of Ca1-xNaxFe2As2

The antiferromagnetic parent compound, CaFe2As2, shows a supression of the spin density wave and a subsequent superconducting state upon partial substitution of Ca by Na. Along the substitution series, superconducting transition temperatures up to ∼35 K were found. We studied the electronic phase diagram of Ca1-xNaxFe2As2 using Moessbauer spectroscopy and muon spin relaxation experiments. We have analyzed the data in terms of magnetic and superconducting properties and possible coexistence of superconductivity and spin density wave order. We compared our results with recently published data of Ba1-xNaxFe2As2.