Magneto-optical characterizations of FeTe₀.₅Se₀.₅ thin films with critical current density over 1 MA/cm²

الأصل · EN

We performed magneto-optical (MO) measurements on FeTe₀.₅Se₀.₅ thin films grown on LaAlO₃ (LAO) and Yttria-stabilized zirconia (YSZ) single-crystalline substrates. These thin films show superconducting transition temperature, Tc 19 K, 4 K higher than the bulk sample. Typical roof-top patterns can be observed in the MO images of thin films grown on LAO and YSZ, from which a large and homogeneous critical current density, Jc, over 1 × 10⁶ A/cm² at 5 K was obtained. Magnetic flux penetration measurement reveals that the current is almost isotropically distributed in the two thin films. Compared with bulk crystals, FeTe₀.₅Se₀.₅ thin film demonstrates not only higher Tc, but also much larger Jc, which is attractive for applications.