Elastic constants and ultrasound attenuation in the spin-liquid phase of Cs₂CuCl₄

الأصل · EN

The spin excitations in the spin-liquid phase of the anisotropic triangular lattice quantum antiferromagnet Cs₂CuCl₄ have been shown to propagate dominantly along the crystallographic b axis. To test this dimensional reduction scenario, we have performed ultrasound experiments in the spin-liquid phase of Cs₂CuCl₄ probing the elastic constant c₂₂ and the sound attenuation along the b axis as a function of an external magnetic field along the a axis. We show that our data can be quantitatively explained within the framework of a nearest-neighbor spin-1/2 Heisenberg chain, where fermions are introduced via the Jordan-Wigner transformation and the spin-phonon interaction arises from the usual exchange-striction mechanism.