Charge fluctuations in small-capacitance junctions

A. N. Cleland; J. M. Schmidt; John Clarke

doi:10.1103/PhysRevLett.64.1565

Charge fluctuations in small-capacitance junctions

A. N. Cleland, J. M. Schmidt, and John Clarke

Phys. Rev. Lett. 64, 1565 – Published 26 March 1990

Abstract

The current-voltage characteristics of submicron normal-metal tunnel junctions at millikelvin temperatures are observed to exhibit a sharp Coulomb blockade with high-resistance thin-film leads, but to be heavily smeared for low-resistance leads. As the temperature is lowered, the zero-bias differential resistance tends asymptotically to a limit that is greater for junctions with high-resistance leads. Both observations are explained in terms of a model in which quantum fluctuations in the external circuit enhance the low-temperature tunneling rate. The predictions are in reasonable agreement with the data.

Received 18 December 1989

DOI:https://doi.org/10.1103/PhysRevLett.64.1565

Authors & Affiliations

A. N. Cleland, J. M. Schmidt, and John Clarke

Department of Physics, University of California, Berkeley, Berkeley, California 94720 an
Materials and Chemical Sciences Division, Lawrence Berkeley Laboratories, Berkeley, California 94720