Evidence for an angular dependent contribution from columnar defects to the equilibrium magnetization of YBa_2Cu_3O_{7-d}

Abstract

We have measured an angle-dependent contribution to the equilibrium magnetization of a YBa_2Cu_3O_{7-d} single crystal with columnar defects created by 5.8GeV Pb ions. This contribution manifests itself as a jump in the equilibrium torque signal, when the magnetic field crosses that of the defects. The magnitude of the signal, which is observed in a narrow temperature interval less than 2K and for fields up to about twice the irradiation field, is used to estimate the the energy gained by vortex pinning on the defects. The vanishing of the effective pinning energy at a temperature below Tc is attributed to its renormalization by thermal fluctuations.

4 pages, 4 figures, submitted to Physical Review B additional comments on the interperation of the results

References in corpus (1)

• Properties of the Bose glass phase in irradiated superconductors near the matching field

Cited by in corpus (3)

• Langevin Dynamics of the vortex matter two-stage melting transition in Bi_2Sr_2CaCu_2O${}_{8+\delta }$ in the presence of straight and of tilted columnar defects
• Thermodynamics of the vortex liquid in heavy ion-irradiated superconductors
• Multiple Changes of Order of the Vortex Melting Transition in BSCCO with Dilute Columnar Defects