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arXiv · 1409.1438

Evidence of surface superconductivity and multi-quanta vortex states in a weakly-pinned single crystal of Ca3Ir4Sn13

Santosh Kumar·Ravi P. Singh·A. Thamizhavel·C. V. Tomy·A. K. Grover
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Abstract

We report here the observation of anomalous paramagnetic signal(s) in the isofield field-cooled cool-down magnetization scans (MFCC(T)) recorded for a single crystal of a low Tc superconductor Ca3Ir4Sn13. Novel features emanating from the MFCC(T) response include an oscillatory magnetization behaviour below Tc and a rich multiplicity (non-uniqueness) in magnetization ranging from diamagnetism to paramagnetism at a given H, T value. The metastability in MFCC(T) has been ascribed to non-unique coexistence of multi-quanta vortex states and single quantum (Abrikosov) vortices. Additionally, the isothermal M(H) scans recorded across a short window of temperature just below Tc show evidence for only the multi-quanta vortex states in the domain of surface superconductivity, with no fingerprint(s) of pinned Abrikosov lattice.

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Santosh Kumar, Ravi P. Singh, A. Thamizhavel, C. V. Tomy, A. K. Grover. 2014-09-04. Evidence of surface superconductivity and multi-quanta vortex states in a weakly-pinned single crystal of Ca3Ir4Sn13. https://arxiv.org/abs/1409.1438

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