BATAS FASA STRUKTUR MESOSKOPIK SUPERKONDUKTOR HIBRID PB/AL
Abstrak: Investigation of the
phase boundary of superconducting Pb/Al hybrid macroscopic and mesoscopic
structures is conducted and reported. The structures consists of 50 nm thin Al
circular disk with 50 nm Pb disk deposited on top of it and 10 nm Ge deposited
in between as insulation layer. Radius of the disk is 4 μm for macroscopic and
1,5 μm for mesoscopic structures. Deposition process was carried out with
bi-layer lift-off electronic beam lithography technique. The measurements are
performed in a 3He bath cryostat with temperature range from below 1 K to less
than 7.19 K (Tc of Pb). Current of 5μA is applied to the sample and the R(T)
measurement is performed for constant magnetic field H. Measurements are done
for several values of magnetic field with a step of 0.1 mT. Field cooled
measurements on macroscopic Al disk with diameter 4 μm and 1,5 μm and 50 nm
thickness were carried out for reference. Results indicates that Pb strongly
screened the field of Al for both macroscopic and mesoscopic samples with
Little-Parks oscillation observed for mesoscopic disk. Tc values of macroscopic
and mesoscopic samples show that superconductivity nucleation is strongly
dependant on samples‟ boundary surface.
Penulis: Elistia Liza Namigo,
Nele Schildermans
Kode Jurnal: jpfisikadd140789
