Influence of a single defect on the conductance of a tunnel point contact between a normal metal and a superconductor

• Veröffentlicht in: Физика низких температур
• Datum: 2008
• Hauptverfasser: Avotina, Ye.S., Kolesnichenko, Yu.A., van Ruitenbeek, J.M.
• Format: Artikel
• Sprache: English
• Veröffentlicht: Фізико-технічний інститут низьких температур ім. Б.І. Вєркіна НАН України 2008
• Schlagworte: Электpонные свойства металлов и сплавов
• Online Zugang: https://nasplib.isofts.kiev.ua/handle/123456789/117881
• Назва журналу: Digital Library of Periodicals of National Academy of Sciences of Ukraine
• Zitieren: Influence of a single defect on the conductance of a tunnel point contact between a normal metal and a superconductor / Ye.S. Avotina, Yu.A. Kolesnichenko, J.M. van Ruitenbeek // Физика низких температур. — 2008. — Т. 34, № 11. — С. 1184-1191. — Бібліогр.: 32 назв. — англ.

We have investigated theoretically the conductance of a normal–superconductor point contact in the tunnel limit and analyzed the quantum interference effects originating from the scattering of quasi-particles by point-like defects. Analytical expressions for the oscillatory dependence of the conductance on the position of the defect are obtained for the defect situated either in the normal metal, or in the superconductor. It is found that the amplitude of oscillations significantly increases when the applied bias approaches the gap energy of the superconductor. The spatial distribution of the order parameter near the surface in the presence of a defect is also obtained.