Lack of static lattice distortion in $Tb_2 Ti_2 O_7$

TL;DR

This study used muon spin resonance to investigate whether temperature-dependent lattice distortions occur in Tb$_2$Ti$_2$O$_7$, finding no evidence for such lattice deformations down to very low temperatures.

Contribution

The paper provides experimental evidence that Tb$_2$Ti$_2$O$_7$ does not exhibit static lattice distortions, clarifying its structural stability at low temperatures.

Findings

Lattice distortions are absent in Tb$_2$Ti$_2$O$_7$.

Field distribution width explained solely by spin susceptibility.

No temperature-dependent hyperfine coupling observed.

Abstract

We investigated the possibility of temperature dependent lattice distortions in the pyrochlore compound Tb$_{2}$Ti$_{2}$O$_{7}$ by measuring the internal magnetic field distribution, using muon spin resonance, and comparing it to the susceptibility. The measurements are done at temperatures as low as 70 mK and external fields up to 6 kG. We find that the evolution of the width of the field distribution can be explained by spin susceptibility only, thus ruling out a temperature dependent hyperfine coupling. We conclude that lattice deformations are absent in Tb$_{2}$Ti$_{2}$O$_{7}$.