Browsing by Subject "superconductivity"

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    Behavior of superconductivity in a Pb/Ag heterostructure
    (2019-09-06) Nam, Hyoungdo; Zhang, Chendong; Lee, Woojoo; Zhu, Siyuan; Gao, Hong-Jun; Niu, Qian; Fiete, Gregory A.; Shih, C. K.
    The superconducting proximity effect is a long-standing topic of great importance in condensed matter physics. A crucial but unresolved issue is which interfacial and material details determine the efficiency of the proximity effect. In this work, we study an epitaxially grown superconductor (SC)/normal metal (NM) heterostructure (Pb/Ag) and find a spatially constant superconducting gap determined by local tunneling spectroscopy and magneto response measurements, despite the highly mismatched Fermi surfaces between individual Pb and Ag epitaxial layers, and the large differences in the lattice constants and electronic density of states in the separate components. The uniform superconducting gap is in contrast to the spatially varying pair potential with a discontinuity at the interface theoretically predicted for an ideal SC-NM junction and experimentally observed previously in several lateral SC-NM junctions. We experimentally verify that the transmission of electrons across the interface in the vertical Pb/Ag heterostructure is high enough that a new band structure emerges even at the single particle level. Our experimental results call for further theoretical work in order to develop predictive power for the proximity effect starting from realistic, material relevant microscopic models.
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    Sterelithography of Ceramics
    (1997) Himmer, T.; Nakagawa, T.; Noguchi, H.
    For studies of Stereolithography of Ceramics (SOC), a composite has been produced by mixing ceramic powder with a photosensitive resin. To obtain high load of ceramics a lamination preprocess was used. Then, the produced ceramic-binder films have been laminated and selectively cured in a Stereolithography machine. After cleaning, the green bodies were fired to burn out the binder and afterwards sintered to achieve full strength.