2025/11/24 by Wang, Xusheng, He, Lianyi, Ji, Shuai-hua
Materials Science · Physics and Astronomy · #FOS: Physical sciences #Iron-based superconductors research #Rare-earth and actinide compounds #Superconductivity (cond-mat.supr-con) #Superconductivity in MgB2 and Alloys
paper · doi:10.48550/arxiv.2511.19030
openalex publication_date 2025/11/24 · openalex created_date 2025/11/27 · openalex updated_date 2026/07/28
Through a comprehensive free energy analysis, we demonstrate that finite temperature can simultaneously weaken superconductivity and mitigate spin polarization induced depairing, leading to potential non-monotonic temperature-dependent behaviors in superconductors subjected to large exchange fields. Remarkably, superconductivity can be counterintuitively enhanced by temperature when the Zeeman energy exceeds the superconducting order parameter, owing to the competition between thermal and magnetic effects. We propose that multiband effect offers one possible microscopic route for this temperature-induced enhancement and demonstrate it explicitly within a two-band superconducting model. A detailed parameter analysis identifies the conditions under which this phenomenon emerges, suggesting that temperature-enhanced superconductivity may be observable in materials such as MgB2 and FeSe through transport and tunneling measurements.