Title :
Evidence for tunneling and magnetic scattering at in situ YBCO/noble-metal interfaces
Author :
Sanders, S.C. ; Russek, S.E. ; Clickner, C.C. ; Ekin, J.W.
Author_Institution :
Div. of Electromagn. Technol., Nat. Inst. of Stand. & Technol., Boulder, CO, USA
fDate :
6/1/1995 12:00:00 AM
Abstract :
We report low-temperature conductance data for in situ YBa/sub 2/Cu/sub 3/O/sub 7-/spl delta// (YBCO)/Ag, YBCO/Au, and YBCO/Pt planar c-axis interfaces. Analysis of the conductance data for these interfaces, which have resistivities as low as 1/spl times/10/sup -8/ /spl Omega//spl middot/cm/sup 2/, indicates that tunneling is the predominant transport mechanism. Zero-bias conductance peaks are present for all of the in situ interfaces. These peaks are analyzed in the framework of the Appelbaum model and are attributed to the presence of isolated magnetic spins at the interface. The presence and similarity of the peaks for each noble-metal overlayer supports the hypothesis that the magnetic spins are inherent to the YBCO surface.<>
Keywords :
barium compounds; contact resistance; high-temperature superconductors; superconductive tunnelling; yttrium compounds; Appelbaum model; YBa/sub 2/Cu/sub 3/O/sub 7-/spl delta//; YBa/sub 2/Cu/sub 3/O/sub 7/-Ag; YBa/sub 2/Cu/sub 3/O/sub 7/-Au; YBa/sub 2/Cu/sub 3/O/sub 7/-Pt; in situ YBCO/noble-metal interfaces; low-temperature conductance; magnetic scattering; magnetic spins; resistivities; superconductor/normal contacts; transport; tunneling; Gold; Government; Magnetic films; Magnetic tunneling; Optical pulses; Pulsed laser deposition; Scattering; Semiconductor films; Voltage; Yttrium barium copper oxide;
Journal_Title :
Applied Superconductivity, IEEE Transactions on
