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arXiv · 2610.34318

Universal Scaling of the Little-Parks Oscillation Amplitude

Yuelin Shen·Zixuan Huang·Xiaoying Xu·Wei Qin·Yufan Li
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Abstract

The Little-Parks effect played a pivotal role in establishing fluxoid quantization in doubly connected superconductors and providing early evidence for electron pairing, central to BCS theory. More recently, it has emerged as an important phase-sensitive probe of superconducting order. Yet the amplitude of the Little-Parks oscillation has never been fully understood theoretically, as the conventional mean-field Ginzburg-Landau description does not account for its pronounced temperature dependence. Here, we develop a universal theoretical framework incorporating thermal fluctuations in reduced-dimensional superconducting rings. By analyzing Little-Parks measurements across multiple superconductors, we show that the resulting scaling quantitatively captures the temperature-dependent oscillation amplitudes over a broad range of materials and device geometries, resolving the long-standing discrepancy between theory and experiment.

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Yuelin Shen, Zixuan Huang, Xiaoying Xu, Wei Qin, Yufan Li. 2026-10-25. Universal Scaling of the Little-Parks Oscillation Amplitude. https://arxiv.org/abs/2610.34318

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