1204.4270 (Xiaofeng Xu et al.)

On the transport and thermodynamic properties of quasi-two-dimensional
purple bronzes A$_{0.9}$Mo$_6$O$_{17}$ (A=Na, K)    [PDF]

Xiaofeng Xu, A. F. Bangura, C. Q. Niu, M. Greenblatt, Song Yue, C. Panagopoulos, N. E. Hussey

We report a comparative study of the specific heat, electrical resistivity and thermal conductivity of the quasi-two-dimensional purple bronzes Na$_{0.9}$Mo$_6$O$_{17}$ and K$_{0.9}$Mo$_6$O$_{17}$, with special emphasis on the behavior near their respective charge-density-wave transition temperatures $T_P$. The contrasting behavior of both the transport and the thermodynamic properties near $T_P$ is argued to arise predominantly from the different levels of intrinsic disorder in the two systems. A significant proportion of the enhancement of the thermal conductivity above $T_P$ in Na$_{0.9}$Mo$_6$O$_{17}$, and to a lesser extent in K$_{0.9}$Mo$_6$O$_{17}$, is attributed to the emergence of phason excitations.

View original: http://arxiv.org/abs/1204.4270