Abstract
We investigate a normal-metal-superconductor (point) contact in the limit where the number of conducting channels in the metallic wire is reduced to few channels. As the effective Fermi energy drops below the gap energy, a conducting band with a width twice the Fermi energy is formed. Depending on the mode of operation, the conduction band can be further squeezed, leading to various nonlinear effects in the current-voltage characteristics such as current saturation, a N-shaped negative differential resistance, bistability, and hysteresis.
Similar content being viewed by others
References
B. van Wees and H. Takayanagi, in Mesoscopic Electron Transport, edited by L. Son et al., NATO ASI Series, Vol. 345, Kluwer, 1997, p. 469, and references therein; C. W. J. Beenakker, in Mesoscopic Quantum Physics, edited by E. Akkermans et al., Elsevier, 1995.
A. F. Andreev, Zh. Éksp. Teor. Fiz. 46, 1823 1964) [Sov. Phys. JETP 19, 1228 (1964)].
G. Blonder, M. Tinkham, and T. M. Klapwijk, Phys. Rev. B 25, 4515 (1982).
Yu. K. Dzhikaev, Zh. Éksp. Teor. Fiz. 68, 295 (1975) [Sov. Phys. JETP 41, 144 (1975)].
G. Wendin and V. S. Shumeiko, Phys. Rev. B 53, R6006 (1996).
G. B. Lesovik, A. L. Fauchére, and G. Blatter, Phys. Rev. B 55, 3146 (1997).
H. Takayanagi, T. Akazaki, and J. Nitta, Phys. Rev. Lett. 75, 3533 (1995).
D. A. Wharam et al., J. Phys. C 21, L20 (1988); B. J. van Wees et al., Phys. Rev. Lett. 60, 848 1988).
A. P. Sutton, Curr. Opin. Solid State Mater. Sci. 1, 827 (1996).
L. I. Glazman and A. V. Khaetskii, Europhys. Lett. 9, 263 (1989); N. K. Patel et al., J. Phys. C 2, 7247 (1990).
R. J. Brown et al., J. Phys. C 1, 6285 (1989).
I. Larkin and J. Davies, Phys. Rev. B 52, R5535 (1995).
C. W. J. Beenakker, Phys. Rev. B 46, 12841 1992).
V. J. Goldman, D. C. Tsui, and J. E. Cunningham, Phys. Rev. Lett. 58, 1256 1987).
Author information
Authors and Affiliations
Additional information
Pis’ma Zh. Éksp. Teor. Fiz. 68, No. 7, 572–577 (10 October 1998)
Published in English in the original Russian journal. Edited by Steve Torstveit.