Vortex Channeling and the V-I Characteristic of YBa2Cu3O7 Low Angle Grain Boundaries

M. J. Hogg; F. Kahlmann; E. J. Tarte; Z. H. Barber; J. E. Evetts

doi:10.1063/1.1351529

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Vortex Channeling and the V-I Characteristic of YBa2Cu3O7 Low Angle Grain Boundaries

M. J. Hogg·F. Kahlmann·E. J. Tarte·Z. H. Barber·J. E. Evetts

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Abstract

We have performed V-I measurements on a thin film YBa2Cu3O7 4^o [001] tilt low angle grain boundary over an extensive range of temperature and field, verifying the presence of a linear characteristic. We report on the occurrence of the linear characteristic in its basic form and on the observation of V-I kinking into several, and in some cases numerous, linear segments. We interpret these findings in terms of a variation in the dissipative width at the grain boundary. Kinking from one linear V-I section to another of different gradient is described in terms of a change in the number of vortex rows being viscously channeled along the boundary.

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M. J. Hogg, F. Kahlmann, E. J. Tarte, Z. H. Barber, J. E. Evetts. 2001-01-19. Vortex Channeling and the V-I Characteristic of YBa2Cu3O7 Low Angle Grain Boundaries. https://doi.org/10.1063/1.1351529

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