Two Dimensional Kagome Correlations and Field Induced Order in the Ferromagnetic XY Pyrochlore Yb2Ti2O7

TL;DR

This study reveals that Yb2Ti2O7 exhibits quasi-2D kagome correlations at low temperatures, which transition to 3D long-range order under modest magnetic fields, mapped through neutron scattering experiments.

Contribution

It provides the first detailed mapping of the low temperature and magnetic field phase diagram of Yb2Ti2O7, highlighting the role of kagome correlations and field-induced order.

Findings

Quasi-2D kagome correlations dominate at low T

Modest magnetic fields induce 3D long-range order

Dispersive spin waves characterize the ordered state

Abstract

Neutron scattering measurements show the ferromagnetic XY pyrochlore Yb2Ti2O7 to display strong quasi-two dimensional (2D) spin correlations at low temperature, which give way to long range order (LRO) under the application of modest magnetic fields. Rods of scattering along < 111 > directions due to these 2D spin correlations imply a magnetic decomposition of the cubic pyrochlore system into decoupled kagome planes. A magnetic field of ~0.5 T applied along the [1-10] direction induces a transition to a 3D LRO state characterized by long-lived, dispersive spin waves. Our measurements map out a complex low temperature-field phase diagram for this exotic pyrochlore magnet.