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Disorder and thermally driven vortex-lattice melting in La{2-x}Sr{x}CuO{4} crystals

Y. Radzyner·A. Shaulov·Y. Yeshurun·I. Felner·K. Kishio·J. Shimoyama
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Abstract

Magnetization measurements in La{2-x}Sr{x}CuO{4} crystals indicate vortex order-disorder transition manifested by a sharp kink in the second magnetization peak. The transition field exhibits unique temperature dependence, namely a strong decrease with temperature in the entire measured range. This behavior rules out the conventional interpretation of a disorder-driven transition into an entangled vortex solid phase. It is shown that the transition in La{2-x}Sr{x}CuO{4} is driven by both thermally- and disorder-induced fluctuations, resulting in a pinned liquid state. We conclude that vortex solid-liquid, solid-solid and solid to pinned-liquid transitions are different manifestations of the same thermodynamic order-disorder transition, distinguished by the relative contributions of thermal and disorder-induced fluctuations.

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Y. Radzyner, A. Shaulov, Y. Yeshurun, I. Felner, K. Kishio, J. Shimoyama. 2001-12-23. Disorder and thermally driven vortex-lattice melting in La{2-x}Sr{x}CuO{4} crystals. https://doi.org/10.1103/physrevb.65.100503

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