Type: Article
Publication Date: 2023-04-21
Citations: 10
DOI: https://doi.org/10.1103/physrevlett.130.166703
Spiral spin liquids are an exotic class of correlated paramagnets with an enigmatic magnetic ground state composed of a degenerate manifold of fluctuating spin spirals. Experimental realizations of the spiral spin liquid are scarce, mainly due to the prominence of structural distortions in candidate materials that can trigger order-by-disorder transitions to more conventionally ordered magnetic ground states. Expanding the pool of candidate materials that may host a spiral spin liquid is therefore crucial to realizing this novel magnetic ground state and understanding its robustness against perturbations that arise in real materials. Here, we show that the material ${\mathrm{LiYbO}}_{2}$ is the first experimental realization of a spiral spin liquid predicted to emerge from the ${J}_{1}\text{\ensuremath{-}}{J}_{2}$ Heisenberg model on an elongated diamond lattice. Through a complementary combination of high-resolution and diffuse neutron magnetic scattering studies on a polycrystalline sample, we demonstrate that ${\mathrm{LiYbO}}_{2}$ fulfills the requirements for the experimental realization of the spiral spin liquid and reconstruct single-crystal diffuse neutron magnetic scattering maps that reveal continuous spiral spin contours---a characteristic experimental hallmark of this exotic magnetic phase.