2025/11/27 by Yusong Zhao, Han, Haowen, Zhao, Yusong +25
Materials Science · Physics and Astronomy · #Magnetic and transport properties of perovskites and related materials #Physics of Superconductivity and Magnetism #Advanced Condensed Matter Physics
paper · pdf · doi:10.48550/arxiv.2511.22026
Recently, preliminary magnetic field-reentrant superconductivity manifested in high-temperature (Tc) Eu-doped infinite-layer (IL) nickelates, beyond analogous discoveries exclusively in low-Tc systems. This evokes intriguing fundamental issues about potential quantum-phase boundary and criticality between unconventional superconductivity and field-reentrant-one, which are inexplicable owing to formidable challenges in growing IL-nickelates towards later-series rare-earths. Herein, we open up chemical avenues to enable effective growth of (RE1-yRE'y)1-xEuxNiO2 (RE/RE': Pr, Nd, Sm, Gd, Dy), giving rise to discoveries of RE-4f-related quantum competition between high-Tc and reentrant superconductivity. Robust magnetic-field-reentrant superconductivity with uniaxial anisotropy is observed at superconducting-dome boundaries, stemming from Eu2+-4f7 associated competition between magnetic-fluctuation promoted pairing and exchange-field interactions. Their quantum-criticality is further modulable via RE(RE')-magnetism, which either reinforces reentrancy or elevates Tc (40.1 K) with more robust critical-current-density (~266 kA/cm2 at 2 K) beyond Sr-/Ca-doped counterparts. Our synthetic route enables the establishment of an ideal platform via IL-nickelates for studying 4f-related unconventional superconductivity and quantum-criticality.