Enhancement of the critical current density in FeO-coated MgB2 thin films at high magnetic fields
نویسندگان
چکیده
The effect of depositing FeO nanoparticles with a diameter of 10 nm onto the surface of MgB(2) thin films on the critical current density was studied in comparison with the case of uncoated MgB(2) thin films. We calculated the superconducting critical current densities (J(c)) from the magnetization hysteresis (M-H) curves for both sets of samples and found that the J(c) value of FeO-coated films is higher at all fields and temperatures than the J(c) value for uncoated films, and that it decreases to ~10(5) A/cm(2) at B = 1 T and T = 20 K and remains approximately constant at higher fields up to 7 T.
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