Magnetoelastics of a spin liquid: X-ray diffraction studies of Tb2Ti2O7 in pulsed magnetic fields

TL;DR

This study uses advanced x-ray diffraction techniques to explore how magnetic fields influence the structure of the spin liquid material Tb2Ti2O7, revealing significant magnetoelastic effects and phase transitions.

Contribution

First high-resolution x-ray diffraction measurements of Tb2Ti2O7 under pulsed magnetic fields, uncovering novel magnetoelastic phenomena and structural phase transitions.

Findings

Observation of anisotropic giant magnetostriction

Restoration of pyrochlore symmetry at low fields

Structural phase transition at high magnetic fields

Abstract

We report high resolution single crystal x-ray diffraction measurements of the frustrated pyrochlore magnet Tb2Ti2O7, collected using a novel low temperature pulsed magnet system. This instrument allows characterization of structural degrees of freedom to temperatures as low as 4.4 K, and in applied magnetic fields as large as 30 Tesla. We show that Tb2Ti2O7 manifests intriguing structural effects under the application of magnetic fields, including strongly anisotropic giant magnetostriction, a restoration of perfect pyrochlore symmetry in low magnetic fields, and ultimately a structural phase transition in high magnetic fields. It is suggested that the magnetoelastic coupling thus revealed plays a significant role in the spin liquid physics of Tb2Ti2O7 at low temperatures.