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arXiv · 1412.2454

Magneto-optical characterizations of FeTe$_{0.5}$Se$_{0.5}$ thin films with critical current density over 1 MA/cm$^2$

Yue Sun·Yuji Tsuchiya·Sunseng Pyon·Tsuyoshi Tamegai·Cheng Zhang·Toshinori Ozaki·Qiang Li
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Abstract

We performed magneto-optical (MO) measurements on FeTe$_{0.5}$Se$_{0.5}$ thin films grown on LaAlO$_3$ (LAO) and Yttria-stabilized zirconia (YSZ) single-crystalline substrates. These thin films show superconducting transition temperature, ${T_c}$ $\sim$ 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, ${J_c}$, over 1 $\times$ 10$^6$ A/cm$^2$ 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, FeTe$_{0.5}$Se$_{0.5}$ thin film demonstrates not only higher ${T_c}$, but also much larger ${J_c}$, which is attractive for applications.

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Yue Sun, Yuji Tsuchiya, Sunseng Pyon, Tsuyoshi Tamegai, Cheng Zhang, Toshinori Ozaki, Qiang Li. 2014-12-08. Magneto-optical characterizations of FeTe$_{0.5}$Se$_{0.5}$ thin films with critical current density over 1 MA/cm$^2$. https://doi.org/10.1088/0953-2048%2F28%2F1%2F015010

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