Department of Physics and Astronomy, McMaster University, Hamilton, Ontario, L8S 4M1, Canada.
Phys Rev Lett. 2010 Aug 13;105(7):077203. doi: 10.1103/PhysRevLett.105.077203.
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 T. 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.
我们报告了使用新型低温脉冲磁体系统对受挫钙钛矿磁体 Tb2Ti2O7 进行的高分辨率单晶 X 射线衍射测量。该仪器允许对结构自由度进行特征描述，温度低至 4.4 K，外加磁场高达 30 T。我们表明，Tb2Ti2O7 在磁场作用下表现出有趣的结构效应，包括强烈各向异性的巨磁致伸缩、在低磁场中恢复完美的钙钛矿对称性，以及最终在高磁场中发生结构相变。有人认为，这种磁弹耦合在 Tb2Ti2O7 的低温自旋液体物理中起着重要作用。
