Dynamical scaling as a signature of multiple phase competition in Yb$_2$Ti$_2$O$_7$

Abstract

Yb 2 Ti 2 O 7 is a celebrated example of a pyrochlore magnet with highly-frustrated, anisotropic exchange interactions. To date, attention has largely focused on its unusual, static properties, many of which can be understood as coming from the competition between different types of magnetic order. Here we use inelastic neutron scattering with exceptionally high energy resolution to explore the dynamical properties of Yb 2 Ti 2 O 7 . We find that spin correlations exhibit dynamical scaling, analogous to behaviour found near to a quantum critical point. We show that the observed scaling collapse can be explained within a phenomenological theory of multiple-phase competition, and confirm that a scaling collapse is also seen in semi-classical simulations of a microscopic model of Yb 2 Ti 2 O 7 . These results suggest a general picture for dynamics in systems with competing ground states.

Giant magnetic in-plane anisotropy and competing instabilities in Na3Co2SbO6

“…1(b)], which precisely cover the Γ-M lines. The streaks are, in fact, quasi-2D objects (independent of Q ⊥ ) in reciprocal space, which correspond to quasi-1D correlations in real space, and they can be viewed as a 2D counterpart of rod-like diffuse scattering in Yb 2 Ti 2 O 7 [64,65], which has been attributed to coexisting FM and AFM correlations [66,67]. Below T N , the body of the star is depleted, including the FM-like diffuse scattering near Γ [Fig.…”