Phononic enhancement and detection of hidden spin-nematicity and dynamics in quantum magnets
Phys. Rev. B 114, 014407 – Published 6 July, 2026
DOI: https://doi.org/10.1103/k46x-yqqn
Abstract
The spin nematic phase, characterized by long-range order of spin quadrupole moments in the absence of dipolar magnetism, presents a significant challenge for conventional experimental detection. We propose a method to detect this elusive order in quantum magnets with an illustration in the spin-1 triangular lattice Mott insulator. By integrating out the phonon degrees of freedom, we obtain a phase diagram with substantially enlarged regions for the spin-nematic and spin-nematic-supersolid phases. We then demonstrate that through the spin-lattice coupling, the emergence of spin nematic order imprints a distinctive signature onto the phonon spectra, providing a clear spectroscopic signature for the quadrupolar order. Our formalism offers a direct and powerful method to uncover the hidden spin nematicity, opening a pathway for diagnosing multipolar orders in quantum magnets.
