N.C. Yeh, W. Jiang, et al.
Physica A: Statistical Mechanics and its Applications
We have used a high-resolution scanning SQUID microscope to directly image conventional (h/2e) Josephson vortices trapped in grain boundaries, and half-integer (h/4e) Josephson vortices trapped at the tricrystal point, of the high- Tc superconductor YBa2Cu3O7-δ grown on tricrystal substrates of SrTiO3. Our observation of the half-integer vortex at the tricrystal point is the first direct demonstration of the positive paramagnetic Meissner effect in a polycrystalline high- Tc film. In addition, our images provide the first direct measurement of the Josephson penetration depth. © 1996 American Physical Society.
N.C. Yeh, W. Jiang, et al.
Physica A: Statistical Mechanics and its Applications
C.C. Chi, L. Krusin-Elbaum, et al.
Physica B+C
F. Lombardi, F. Tafuri, et al.
Physical Review Letters
J. Mannhart, M. Scheuermann, et al.
Applied Physics Letters