The London theory of the crossing-vortex lattice in highly anisotropic layered superconductors

Abstract

A novel description of Josephson vortices (JVs) crossed by the pancake vortices (PVs) is proposed on the basis of the anisotropic London theory. The field distribution of a JV and its energy have been calculated for both dense ($a<{\lambda }_J$) and dilute ($a>{\lambda }_J$) PV lattices with distance $a$ between PVs, and the nonlinear JV core size ${\lambda }_J$. It is shown that the ``shifted'' PV lattice (PVs displaced mainly along JVs in the crossing vortex lattice structure), formed in high out-of-plane magnetic fields transforms into the PV lattice ``trapped'' by the JV sublattice at a certain field, lower than ${\Phi }_0/{\gamma }^2{s}^2$, where ${\Phi }_0$ is the flux quantum, $\gamma$ is the anisotropy parameter and $s$ is the distance between CuO${}_2$ planes. With further decreasing $B_z$, the free energy of the crossing vortex lattice structure (PV and JV sublattices coexist separately) can exceed the free energy of the tilted lattice (common PV-JV vortex structure) in the case of $\gamma s<{\lambda }_{ab}$ with the in-plane penetration depth ${\lambda }_{ab}$ if the low ($B_x<\gamma {\Phi }_0/{\lambda }_{ab}^2$) or high ($B_x\gtrsim {\Phi }_0/\gamma s^2$) in-plane magnetic field is applied. It means that the crossing vortex structure is realized in the intermediate field orientations, while the tilted vortex lattice can exist if the magnetic field is aligned near the $c$-axis and the $ab$-plane as well. In the intermediate in-plane fields $\gamma {\Phi }_0/{\lambda }_{ab}^2\lesssim B_x\lesssim {\Phi }_0/\gamma s^2$, the crossing vortex structure with the ``trapped'' PV sublattice seems to settle in until the lock-in transition occurs since this structure has the lower energy with respect to the tilted vortex structure in the magnetic field $\vec{H}$ oriented near the $ab$-plane.

15 pages, 6 figures, accepted for publication in PRB

References in corpus (1)

• Vortex Matter Transition in Bi${}_2$Sr${}_2$CaCu${}_2$O${}_{8+y}$ under Tilted Fields

Cited by in corpus (10)

• Decoration of Josephson Vortices by Pancake Vortices in Bi2Sr2CaCu2Ox
• Generation of tunable Terahertz out-of-plane radiation using Josephson vortices in modulated layered superconductors
• Josephson vortices and solitons inside pancake vortex lattice in layered superconductors
• Phase Transitions in Isolated Vortex Chains
• Strong 3D correlations in vortex system of Bi2212:Pb
• Composite to tilted vortex lattice transition in $B{i}_{2}S{r}_{2}CaC{u}_2{O}_{8+\delta }$ in oblique fields
• Resonance effects due to the excitation of surface Josephson plasma waves in layered superconductors
• Anisotropy of Vortex-Liquid and Vortex-Solid Phases in Single Crystals of Bi${}_2$Sr${}_2$CaCu${}_2$O${}_{8+\delta }$: Violation of the Scaling Law
• Enhanced Transmission of Terahertz Radiation through Periodically Modulated Slabs of Layered Superconductors
• Dependence of vortex phase transitions in mesoscopic BSCCO superconductor at tilted magnetic fields