Title :
BCS-like gap structure of HgBa/sub 2/CuO/sub 4+/spl delta// tunnel junctions
Author :
Jun Chen ; Zasadzinski, J.F. ; Gray, K.E. ; Wagner, J.L. ; Hinks, D.G. ; Kouznetsov, K. ; Coffey, L.
Author_Institution :
Div. of Mater. Sci., Argonne Nat. Lab., IL, USA
fDate :
6/1/1995 12:00:00 AM
Abstract :
We report point-contact tunneling into polycrystalline HgBa/sub 2/CuO/sub 4+/spl delta// superconductors with a T/sub c/ onset of 97 K using a superconducting Nb counterelectrode. These SIS´ tunnel junctions are of unusually high quality for cuprate superconductors, exhibiting low and flat sub-gap conductances and sharp conductance peaks as expected from a BCS density of states. These features are obtained reproducibly and are consistent with earlier published SIN results using a Au counterelectrode. Use of experimental data to simulate performance of a quasiparticle mixer indicates HgBa/sub 2/CuO/sub 4+/spl delta// may be suitable for use in low noise heterodyne receivers operating at a few THz.<>
Keywords :
barium compounds; electronic density of states; high-temperature superconductors; mercury compounds; submillimetre wave receivers; superconducting energy gap; superconducting transition temperature; superconductive tunnelling; superconductor-insulator-superconductor mixers; 97 K; BCS density of states; BCS-like gap structure; HgBa/sub 2/CuO/sub 4+/spl delta//; HgBa/sub 2/CuO/sub 4/; Nb superconducting counterelectrode; critical temperature; low noise heterodyne receivers; point-contact tunneling; quasiparticle mixer; High temperature superconductors; Josephson junctions; Materials science and technology; Niobium; Silicon compounds; Superconducting device noise; Superconducting devices; Superconducting materials; Superconductivity; Tunneling;
Journal_Title :
Applied Superconductivity, IEEE Transactions on
