Nonuniform and coherent motion of superconducting vortices in the picometer-per-second regime
Autor: | Barry Barker, Hui Wang, Jonghee Lee, Helmuth Berger, Michael Dreyer |
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Rok vydání: | 2009 |
Předmět: |
Vortex Lattice
Barrier FOS: Physical sciences Superconducting magnet law.invention Superconductivity (cond-mat.supr-con) law Condensed Matter::Superconductivity Mesoscale and Nanoscale Physics (cond-mat.mes-hall) Condensed Matter - Statistical Mechanics Superconductivity Physics Microscopy Condensed matter physics Condensed Matter - Mesoscale and Nanoscale Physics Statistical Mechanics (cond-mat.stat-mech) Condensed Matter - Superconductivity Vorticity Condensed Matter Physics Electronic Optical and Magnetic Materials Magnetic field Vortex Quantum Gases (cond-mat.quant-gas) Scanning tunneling microscope Condensed Matter - Quantum Gases Pinning force Type-II superconductor |
DOI: | 10.48550/arxiv.0902.0452 |
Popis: | We investigated vortex dynamics in a single-crystal sample of type-II superconductor NbSe$_{2}$ using scanning tunneling microscopy at 4.2 K. The decay of the magnetic field at a few nT/s in our superconducting magnet induced the corresponding motion of vortices at a few pm/s. Starting with an initial magnetic field of 0.5 T, we continued to observe motion of vortices within a field of view of 400$\times$400 nm$^2$ subject to decay of the magnetic field over a week. Vortices moved collectively, and maintained triangular lattices due to strong vortex-vortex interactions during the motion. However, we observed two peculiar characteristics of vortex dynamics in this superconductor. First, the speed and direction of the vortex lattice motion were not uniform in time. Second, despite the non-uniform motion, we also found that there exists an energetically favored configuration of the moving vortices in the single-crystal sample of NbSe$_{2}$ based on the overlaid trajectories and their suppressed speeds. We model the system with weak bulk pinning, strong bulk pinning, and edge barrier effects. Comment: 6 pages, 4 figures, Physical Review B (R) in press (2011) |
Databáze: | OpenAIRE |
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