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arXiv · 1003.4688

Observation of a first-order phase transition deep within the vortex-solid region of YBa2Cu3O7

M. Reibelt·S. Weyeneth·A. Erb·A. Schilling
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Abstract

We have investigated the magnetic phase diagram of a fully oxygenated detwinned YBa2Cu3O7 single crystal by means of magneto-caloric and magnetization measurements, and found thermodynamic evidence for a temperature dependent first-order phase-transition line deep within the vortex-solid region. The associated discontinuities in the entropy are apparently proportional to the magnetic flux density, which may hint at a structural transition of the vortex lattice.

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M. Reibelt, S. Weyeneth, A. Erb, A. Schilling. 2011-09-27. Observation of a first-order phase transition deep within the vortex-solid region of YBa2Cu3O7. https://doi.org/10.1088/0953-2048%2F24%2F10%2F105019

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