VORTEX STATE IN D-WAVE SUPERCONDUCTIVITY

After a brief introduction on d-wave superconductivity, we review some unusual properties of vortex and vortex lattice in d-wave superconduc tivity. In a magnetic field B parallel to c a square vortex lattice ti lted by 45 degrees from the a-axis is most stable except in the immedi ate vicinity of T-c the superconducting transition temperature ol in a small magnetic field (say B less than or equal to 1 T). Further in th e vortex core, there are low-energy extended states (say \E\ < 0.2 Del ta) and a few bound states in contrast to the dense series of bound st ates in a vortex of conventional superconductors. In a magnetic field B in the a-b plane, both thermodynamic and transport properties exhibi t fourfold symmetry, which should be readily accessible experimentally . (C) 1998 Elsevier Science B.V. All rights reserved.