Physics News

The Key Laboratory of Applied Superconductivity, Institute of Electrical Engineering, Chinese Academy of Sciences, Beijing, and China Research have collaborated to reveal the heat treatment effects on the superconducting properties of Ag-doped Sr0.6K0.4Fe2As2 compounds. Because of its significant research value, the study is reported in issue 7 of SCIENCE CHINA Physics, Mechanics & Astronomy.Previously, our group studied the effect of adding Ag to polycrystalline Sr0.6K0.4Fe2As2 and found that the critical current density Jc and the irreversibility field increase markedly. More recently, Wang et al. published the first report of significant transport of critical currents in Sr0.6K0.4Fe2As2 wires and tapes when Ag is used as an additive and a sheath material.However, to our knowledge, systematic reports on the relationship between sample preparation, microstructure, and the superconducting properties of polycrystalline pnictide superconductors are very rare. In fact, the critical properties of superconduct