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DOE OSTI · 1806598

Magnetic excitations in infinite-layer nickelates

Lu, H.·Rossi, M.·Nag, A.·Osada, M.·Li, D. F.·Lee, K.·Wang, B. Y.·Garcia-Fernandez, M.·Agrestini, S.·Shen, Z. X.·Been, E. M.·Moritz, B.·Devereaux, T. P.·Zaanen, J.·Hwang, H. Y.·Zhou, Ke-Jin·Lee, W. S.
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Abstract

The discovery of superconductivity in infinite-layer nickelates brings us tantalizingly close to a material class that mirrors the cuprate superconductors. We measured the magnetic excitations in these nickelates using resonant inelastic x-ray scattering at the Ni L 3 -edge. Undoped NdNiO 2 possesses a branch of dispersive excitations with a bandwidth of approximately 200 milli–electron volts, which is reminiscent of the spin wave of strongly coupled, antiferromagnetically aligned spins on a square lattice. The substantial damping of these modes indicates the importance of coupling to rare-earth itinerant electrons. Upon doping, the spectral weight and energy decrease slightly, whereas the modes become overdamped. Our results highlight the role of Mottness in infinite-layer nickelates.

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75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITYRIXSmagnetic excitationsuperconductivity

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Lu, H., Rossi, M., Nag, A., Osada, M., Li, D. F., Lee, K., Wang, B. Y., Garcia-Fernandez, M., Agrestini, S., Shen, Z. X., Been, E. M., Moritz, B., Devereaux, T. P., Zaanen, J., Hwang, H. Y., Zhou, Ke-Jin, Lee, W. S.. 2021-07-08. Magnetic excitations in infinite-layer nickelates. https://doi.org/10.1126/science.abd7726

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