Proceedings of the 3^rd European Workshop on Low Temperature Electronics
WOLTE 3

J. Phys. IV France 08 (1998) Pr3-289-Pr3-292
DOI: 10.1051/jp4:1998364

Effects induced by electron beam irradiation on the properties of Y₁Ba₂Cu₃O_7-x biepitaxial Josephson junctions

F. Tafuri^{1, 2}, B. Nadgorny^{3, 4}, S. Shokhor³, M. Gurvitch³, F. Lombardi², F. Carillo² and A. Di Chiara<sup>2

1</sup>  Dipartimento di Ingegneria dell'Informazione, Seconda Università di Napoli, Aversa (CE), Italy
²  INFM, Dipartimento di Scienze Fisiche, Università di Napoli Federico II, Napoli, Italy
³  Department of Physics, State University of New York at Stony Brook, Stony Brook, New York 11794, U.S.A.
⁴  Naval Research Laboratory, Washington DC 20375, U.S.A.

Abstract
The properties of the Y₁Ba₂Cu₃O_7-x biepitaxial Josephson junctions were reproducibly modified by a focused electron beam irradiation of the interface region. The original structures are based on 45° a-axis tilt grain boundaries. The junction parameters can be controllably adjusted by applying an appropriate irradiation dose. Electron irradiation reduced the critical current of the junctions and increased the normal state specific resistivity. The disappearance of the excess current and the shift of the voltage position of the Fiske steps were also observed. Isothermal annealing partly restores the original junction properties. Some aspects of the nature of the grain boundary barriers can be better understood from the study of the properties of irradiated junctions.

© EDP Sciences 1998