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STM Imaging of Flux Line Arrangements in the Peak Effect Regime

A. M. Troyanovski·M. van Hecke·N. Saha·J. Aarts·P. H. Kes
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Abstract

We present the results of a study of vortex arrangements in the peak-effect regime of 2H-NbSe_2 by scanning tunneling microscopy. By slowly increasing the temperature in a constant magnetic field, we observed a sharp transition from collective vortex motion to positional fluctuations of individual vortices at the temperature which coincides with the onset of the peak effect in ac-susceptibility. We conclude that the peak effect is a disorder driven transition, with the pinning energy winning from the elastic energy.

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A. M. Troyanovski, M. van Hecke, N. Saha, J. Aarts, P. H. Kes. 2002-07-04. STM Imaging of Flux Line Arrangements in the Peak Effect Regime. https://doi.org/10.1103/physrevlett.89.147006

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