We report a study on the thermal conductivity (\kappa) of Tb_2Ti_2O_7 single crystals at low temperatures. It is found that in zero field this material has an extremely low phonon thermal conductivity in a broad temperature range. The mean free path of phonons is even smaller than that of amorphous materials and is 3--4 orders of magnitude smaller than the sample size at 0.3 K. The strong spin fluctuation of the spin-liquid state is discussed to be the reason of the strong phonon scattering. The magnetic-field dependence of \kappa and comparison with Y_2Ti_2O_7 and TbYTi_2O_7 confirm the magnetic origin of this phonon-glass-like behavior.
@article{arxiv.1305.6853,
title = {Magnetically originated phonon-glass-like behavior in Tb_2Ti_2O_7 single crystal},
author = {Q. J. Li and Z. Y. Zhao and C. Fan and F. B. Zhang and H. D. Zhou and X. Zhao and X. F. Sun},
journal= {arXiv preprint arXiv:1305.6853},
year = {2013}
}
Comments
7 pages, 4 figures, accepted for publication in Phys. Rev. B