Spin-glass state in nickelate superconductors

Saykin, David R. [SLAC National Accelerator Laboratory (SLAC), Menlo Park, CA (United States). Stanford Institute for Materials and Energy Science (SIMES); Stanford Univ., CA (United States)]; Gonzalez, Martin [SLAC National Accelerator Laboratory (SLAC), Menlo Park, CA (United States). Stanford Institute for Materials and Energy Science (SIMES); Stanford Univ., CA (United States)]; Fowlie, Jennifer [SLAC National Accelerator Laboratory (SLAC), Menlo Park, CA (United States). Stanford Institute for Materials and Energy Science (SIMES); Stanford Univ., CA (United States)]; Kivelson, Steven A. [Stanford Univ., CA (United States)]; Hwang, Harold Y. [SLAC National Accelerator Laboratory (SLAC), Menlo Park, CA (United States). Stanford Institute for Materials and Energy Science (SIMES); Stanford Univ., CA (United States)]; Kapitulnik, Aharon

doi:10.1038/s41535-025-00813-z

DOE OSTI · 2588632

Spin-glass state in nickelate superconductors

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Abstract

Magneto-optical measurements in La 0.8 Sr 0.2 NiO 2 and Nd 0.825 Sr 0.175 NiO 2 reveal an intriguing new facet of infinite-layer nickelate superconductors: the onset of spin-glass behavior at a temperature far exceeding the superconducting critical temperature T c . This discovery sharply contrasts with copper oxide superconductors, where magnetism and superconductivity remain largely exclusive. Moreover, the magnitude and onset temperature of the polar Kerr effect in Nd 0.825 Sr 0.175 NiO 2 fabricated on SrTiO 3 and (LaAlO 3 ) 0.3 (Sr 2 TaAlO 6 ) 0.7 substrates differ dramatically, while T c does not.

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FOS: Physical sciences Magnetic properties and materials Magneto-optics Materials Science Phase transitions and critical phenomena Strongly Correlated Electrons Superconducting properties and materials Superconductivity Surfaces, interfaces and thin films

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Saykin, David R. [SLAC National Accelerator Laboratory (SLAC), Menlo Park, CA (United States). Stanford Institute for Materials and Energy Science (SIMES); Stanford Univ., CA (United States)], Gonzalez, Martin [SLAC National Accelerator Laboratory (SLAC), Menlo Park, CA (United States). Stanford Institute for Materials and Energy Science (SIMES); Stanford Univ., CA (United States)], Fowlie, Jennifer [SLAC National Accelerator Laboratory (SLAC), Menlo Park, CA (United States). Stanford Institute for Materials and Energy Science (SIMES); Stanford Univ., CA (United States)], Kivelson, Steven A. [Stanford Univ., CA (United States)], Hwang, Harold Y. [SLAC National Accelerator Laboratory (SLAC), Menlo Park, CA (United States). Stanford Institute for Materials and Energy Science (SIMES); Stanford Univ., CA (United States)], Kapitulnik, Aharon. 2025-08-28. Spin-glass state in nickelate superconductors. https://doi.org/10.1038/s41535-025-00813-z

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