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arXiv · 1502.06395

Paramagnetic magnetization signals and curious metastable behaviour in field-cooled magnetization of a single crystal of superconductor 2H-NbSe2

Santosh Kumar·C. V. Tomy·G. Balakrishnan·D. McK Paul·A. K. Grover
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Abstract

We present here some newer characteristics pertaining to paramagnetic Meissner effect like response in a single crystal of the low Tc superconducting compound 2H-NbSe2 via a detailed study of effects of perturbation on the field-cooled magnetization response. In the temperature range, where an anomalous paramagnetic magnetization occurs, the field-cooled magnetization response is found to be highly metastable: it displays a curious tendency to switch randomly from a given paramagnetic value to a diamagnetic or to a different paramagnetic value, when the system is perturbed by an impulse of an externally applied ac field. The new facets revealed in a single crystal of 2H-NbSe2 surprisingly bear a marked resemblance with the characteristics of magnetization behaviour anticipated for the giant vortex states with multiple flux quanta predicted to occur in mesoscopic-sized superconducting specimen and possible transitions amongst such states.

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Santosh Kumar, C. V. Tomy, G. Balakrishnan, D. McK Paul, A. K. Grover. 2015-02-23. Paramagnetic magnetization signals and curious metastable behaviour in field-cooled magnetization of a single crystal of superconductor 2H-NbSe2. https://arxiv.org/abs/1502.06395

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