Magnetic Properties of Eu_x Ca_(1-x) Fe_2 As_2 (0 ≤ x ≤ 1) Superconductor

We have investigated the evolution of magnetic properties of EuxCa1−xFe2As2 (0 ≤ x ≤ 1) materials at different Eu-content (x). The magnetic susceptibility increases while lowering the temperature, showing a typical paramagnetic behavior. There exists a sharp anomaly near 15 - 19 K that arises due to the Eu2+ antiferromagnetic ordering. The temperature dependence of the susceptibility data is analyzed using the Curie-Weiss model and determined the best-fit parameters, the Curie constant (C) and Weiss-temperature (θ) at different x. We found that both parameters, C and θ, vary almost linearly with x. The obtained results are compared with other published data, and their physical implications will be discussed.