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DOE OSTI · 1889441

Spin liquid state in a rare-earth hyperkagome lattice

Abstract

We report quantum fluctuations enhanced by frustration and subtle interplay between competing degrees of freedom offer an ideal ground to realize novel states with fractional quantum numbers in quantum materials that defy standard theoretical paradigms. Quantum spin liquid (QSL) is a highly entangled state wherein frustration-induced strong quantum fluctuations preclude symmetry-breaking phase transitions down to zero temperature without any order parameter. Experimental realizations of QSL in quantum materials with spin dimensionality greater than one is very rare. Here, we present our thermodynamic, nuclear magnetic resonance, muon spin relaxation, and inelastic neutron scattering studies of a rare-earth hyperkagome compound Li 3 Yb 3 Te 2 O 12 in which Yb 3+ ions constitute a three-dimensional spin lattice without any detectable disorder. Our comprehensive experiments evince neither signature of magnetic ordering nor spin freezing down to 38 mK that suggest the realization of dynamic liquid-like ground state in this antiferromagnet. The ground state of this material is interpreted by a low energy J eff = 1/2 degrees of freedom with short-range spin correlations. The present results demonstrate a viable basis to explore spin-orbit driven enigmatic correlated quantum states in a class of rare-earth-based three-dimensional frustrated magnets that may open avenues in theoretical and experimental search for spin liquids.

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BibTeXRIS

Khatua, J., Bhattacharya, S., Ding, Q. P., Vrtnik, S., Strydom, A. M., Butch, N. P., Luetkens, H., Kermarrec, E., Rao, M. Ramachandra, Zorko, A., Furukawa, Y., Khuntia, P.. 2022-09-06. Spin liquid state in a rare-earth hyperkagome lattice. https://doi.org/10.1103/physrevb.106.104404

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