Fractional vortices in Josephson Junction Arrays with π junctions
Abstract
We describe a new set of excitations in the XY model which we call `fractional vortices.' From this definition, we derive an analytical expression for the interaction energy of a pair of bound fractional vortices and verify it numerically. We also use these excitations to suggest a simple ansatz for the ground state of a Josephson Junction array containing π junctions. The ground state for a chain of π junctions is found to be characterized by pairs of fractional vortices of opposite signs. The ground state energy and the phase configuration calculated using this ansatz agree well with results from simulations. The possibility of using these excitations to describe the ground state of a triangular superconducting inclusion in a d-wave superconductor is also discussed. Work supported in part by NSF and NASA.
- Publication:
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APS March Meeting Abstracts
- Pub Date:
- March 2000
- Bibcode:
- 2000APS..MARM12004K