Interacting crossing vortex lattices in the presence of quenched disorder

• Published in: Physica. C, Superconductivity Vol. 412; pp. 372 - 378
• Main Authors: Bending, S.J., Grigorenko, A.N., Crisan, I.A., Cole, D., Koshelev, A.E., Clem, John R., Tamegai, T., Ooi, S.
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.10.2004
• Subjects: Crossing lattices; Layered superconductors; Vortex pumps; Vortices; Vortex pumps; Layered superconductors; Vortices; Crossing lattices; 74.72.−h; 74.60.−w; 74.25.Ha
• ISSN: 0921-4534; 1873-2143
• DOI: 10.1016/j.physc.2004.01.058

We have used high resolution scanning Hall probe microscopy (SHPM) to study vortex structures in the interacting crossing lattices regime of Bi 2Sr 2CaCu 2O 8+ δ (BSCCO) single crystals under independently applied H c and H ∥ fields. At very low c-axis fields we observe a novel 1D vortex chain state where all pancake vortex (PV) stacks become trapped on underlying stacks of Josephson vortices (JVs). In this regime distortions of the JV lattice, induced by varying H ∥, enable the indirect manipulation of PVs trapped on them. Preliminary results of experiments are presented in which we have attempted to realise a vortex `lens' based on this vortex `pump' principle. The existence of 1D vortex chains also explains many of the features observed in the magnetisation of BSCCO under strongly tilted magnetic fields. Finally we demonstrate how the presence of quenched disorder leads to indirect JV pinning via interactions with weakly pinned PV stacks and show how fragmentation of both PV and JV stacks can occur when stacks of JVs `decorated' with PVs are forced abruptly through regions of disorder.