J. Phys. Soc. Jpn. 84, 043704 (2015) [4 Pages]
LETTERS

Commensurate and Incommensurate Vortex States Confined in Mesoscopic Triangles of Weak Pinning Superconducting Thin Films

+ Affiliations
1Department of Engineering Science, University of Electro-Communications, Chofu, Tokyo 182-8585, Japan2Advanced Science Research Center, Japan Atomic Energy Agency, Tokai, Ibaraki 319-1195, Japan3Institute for Materials Research, Tohoku University, Sendai 980-8577, Japan

We report on the direct observation of vortex states confined in equilateral and isosceles triangular dots of weak pinning amorphous superconducting thin films with a scanning superconducting quantum interference device microscope. The observed images illustrate not only pieces of a triangular vortex lattice as commensurate vortex states, but also incommensurate vortex states including metastable ones. We comparatively analyze vortex configurations found in different sample geometries and discuss the symmetry and stability of commensurate and incommensurate vortex configurations against deformations of the sample shape.

©2015 The Physical Society of Japan

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