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arXiv · 0803.0880

Quasi-static and dynamic order-disorder transition in presence of strong pinning

A. V. Bondarenko·A. A. Zavgorodniy·D. A. Lotnik·M. A. Obolenskii·R. V. Vovk·Y. Biletskiy
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Abstract

We present the results of an experimental study of vortex dynamics in non-twinned $YBa_2Cu_3O_{6,87}$ crystal. It is found that critical currents $J_c$ and $J_{c,dyn}$, which correspond to the pinning force in the thermal creep and flux flow mode, respectively, non-monotonically vary with the magnetic field. However, the minimum in the $J_{c,dyn}(H)$ dependence is observed in higher fields, compared with the minimum position $H_{OD}$ in the $J_c(H)$ dependence. Considering that the field $H_{OD}$ corresponds to the static order-disorder transition, this difference is explained by partial dynamic ordering of the vortex solid. It is concluded that finite transverse barriers guarantee finite density of transverse displacements of vortex lines $u_t\simeq c_La_0$ suitable for preservation of the disordered state of the moving vortex solid.

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A. V. Bondarenko, A. A. Zavgorodniy, D. A. Lotnik, M. A. Obolenskii, R. V. Vovk, Y. Biletskiy. 2008-03-07. Quasi-static and dynamic order-disorder transition in presence of strong pinning. https://arxiv.org/abs/0803.0880

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