Slowing down Josephson vortex lattice in Bi_2Sr_2CaCu_2O_{8+d} with pancake vortices

Abstract

We study theoretically and experimentally influence of pancake vortices on motion of the Josephson vortex lattice in layered high-temperature superconductors. Mobility of the Josephson vortices in layered superconductors is strongly suppressed by small amount of pancake-vortex stacks. Moving Josephson vortex lattice forces oscillating zigzag deformation of the pancake-vortex stacks contributing to damping. The salient feature of this contribution is its nonmonotonic dependence on the lattice velocity and the corresponding voltage. Maximum pancake effect is realized when the Josephson frequency matches the relaxation frequency of the stacks. The pancake-vortex damping is strongly suppressed by thermal fluctuations of the pancake vortices. This theoretical picture was qualitatively confirmed by experiments on two mesas prepared out of Bi_2Sr_2CaCu_2O_{8+d} whiskers. We found that the Josephson-vortex flux-flow voltage is very sensitive to small c-axis magnetic field. The pancake-vortex contribution to the current indeed nonmonotonically depends on voltage and decreases with increasing temperature and in-plane magnetic field. We also found that irradiation with heavy ions has no noticeable direct influence on motion of the Josephson vortices but dramatically reduces the pancake-vortex contribution to the damping of the Josephson vortex lattice at low temperatures.

arXiv comment9 pages, 9 figures, accepted to Phys. Rev. B

References in corpus (9)

• Crossing lattices, vortex chains, and angular dependence of melting line in layered superconductors
• Decoration of Josephson Vortices by Pancake Vortices in Bi2Sr2CaCu2Ox
• Columnar defects and vortex fluctuations in layered superconductors
• Dynamic structure selection and instabilities of driven Josephson lattice in high-temperature superconductors
• Josephson vortices and solitons inside pancake vortex lattice in layered superconductors
• Entropy, vortex interactions, and the phase diagram of heavy-ion irradiated Bi_2Sr_2CaCu_2O_8
• Vortex Chains in Anisotropic Superconductors
• Evaporation of the pancake-vortex lattice in weakly-coupled layered superconductors
• Reduction of the Superfluid Density in the Vortex-Liquid Phase of Bi2Sr2CaCu2Oy

Cited by in corpus (3)

• Fluctuating pancake vortices revealed by dissipation of Josephson vortex lattice
• Coexisting multiple dynamic states generated by magnetic field in Bi-2212 stacked Josephson junctions
• In-plane field-induced vortex liquid correlations in underdoped Bi_2Sr_2CaCu_2O_8+δ