Magnetic field induced enlargement of the regime of critical fluctuations in the classical superconductor V3Si from high-resolution specific heat experiments

Y. Zheng; Y. Liu; N. Toyota; R. Lortz

doi:10.1088/0953-8984/27/7/075701

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arXiv · 1409.8358

Magnetic field induced enlargement of the regime of critical fluctuations in the classical superconductor V3Si from high-resolution specific heat experiments

Y. Zheng·Y. Liu·N. Toyota·R. Lortz

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Abstract

We report high-resolution specific heat data on a high-quality single crystal of the classical superconductor V3Si, which reveal tiny lambda-shape anomalies appearing superimposed onto the BCS specific heat jump at the superconducting transition in magnetic fields of 2 T and higher. The appearance of these anomalies is accompanied by a magnetic-field-induced broadening of the superconducting transition. We demonstrate, using scaling relations predicted by the fluctuation models of the 3d-XY and the 3d-Lowest-Landau-Level (3d-LLL) universality class, that the effect of critical fluctuations becomes experimentally observable due to of a magnetic field-induced enlargement of the regime of critical fluctuations. The scaling indicates that a reduction of the effective dimensionality due to the confinement of quasiparticles into low Landau levels is responsible for this effect.

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Y. Zheng, Y. Liu, N. Toyota, R. Lortz. 2014-09-30. Magnetic field induced enlargement of the regime of critical fluctuations in the classical superconductor V3Si from high-resolution specific heat experiments. https://doi.org/10.1088/0953-8984/27/7/075701

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