Sound attenuation in the hyperhoneycomb Kitaev spin liquid

Abstract

Here, the authors propose that phonon dynamics can be exploited to look for the signatures of fractionalization in three-dimensional Kitaev spin liquids. Motivated by recent studies of the hyperhoneycomb Kitaev material $\ensuremath{\beta}$-Li${}_{2}$IrO${}_{3}$, they compute the sound attenuation in the spin-phonon coupled Kitaev model on the hyperhoneycomb lattice, in which Majorana fermions have nodal-line band structure. They show that at low temperatures its angular dependence displays a characteristic pattern, which opens the possibility of detecting the proximity to the Kitaev spin liquid phase in this compound in ultrasound experiments.