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arXiv · 2407.00715

A novel reentrant susceptibility due to vortex and magnetic dipole interaction in a La1.85Sr0.15CuO4 and Gd2O3 composite system

Biswajit Dutta·A. Banerjee
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Abstract

A reentrant behavior of temperature dependent magnetic ac-susceptibility (or excess susceptibility(ES)) at lower temperature is observed in a composite made of superconductor $La_{1.85}Sr_{0.15}CuO_4$ (LCu) and an insulating paramagnetic salt $Gd_2O_3$ (GdO). The ES exhibits an exponential characteristic that varies with temperature ($\exp,[\frac{T_0}{T}]$), T0 is characteristics temperature. The characteristics temperature,T$_0$, decreases as the effective interface diminishes and the amplitude of the dc magnetic field increases. The creation of ferromagnetic dimers between Gd$^{+3}$ ions in GdO is observed as a result of vortex-dipole interaction, which causes the observation of this unusual ES at temperatures much lower than the superconducting onset temperature T$_{S}^{onset}$. This type of ferromagnetic dimer formation much below superconducting transition temperature is found comparable with the formation of Yu-Shiba-Rusinov (YSR) state and interaction between these YSR state.

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Biswajit Dutta, A. Banerjee. 2024-06-30. A novel reentrant susceptibility due to vortex and magnetic dipole interaction in a La1.85Sr0.15CuO4 and Gd2O3 composite system. https://arxiv.org/abs/2407.00715

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