Synthesis of as-grown superconducting MgB_2 thin films by molecular beam epitaxy in UHV conditions

Y. Harada; M. Udsuka; Y. Nakanishi; M. Yoshizawa

doi:10.1016/j.physc.2004.02.229

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Synthesis of as-grown superconducting MgB_2 thin films by molecular beam epitaxy in UHV conditions

Y. Harada·M. Udsuka·Y. Nakanishi·M. Yoshizawa

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Abstract

As-grown superconducting MgB_2 thin films have been grown on SrTiO_3(001), MgO(001), and Al_2O_3(0001) substrates by a molecular beam epitaxy (MBE) method with novel co-evaporation conditions of low deposition rate in ultra-high vacuum. The structural and physical properties of the films were studied by RHEED, XRD, electrical resistivity measurements, and SQUID magnetometer. The RHEED patterns indicate three-dimensional growth for MgB_2. The highest T_c determined by resistivity measurement was about 36K in these samples. And a clear Meissner effect below T_c was observed using magnetic susceptibility measurement. We will discuss the influence of B buffer layer on the structural and physical properties.

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Y. Harada, M. Udsuka, Y. Nakanishi, M. Yoshizawa. 2004-04-11. Synthesis of as-grown superconducting MgB_2 thin films by molecular beam epitaxy in UHV conditions. https://doi.org/10.1016/j.physc.2004.02.229

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