Abstract
The charge-density-wave (CDW) transitions in compounds element) have been studied by x-ray-diffraction and electrical conductivity experiments for temperatures between 20 and 300 K. At incommensurate CDW’s with develop in compounds with R=Ho, Er, Tm, and while commensurate CDW’s develop in compounds with and varies between 83 K in R=Lu and 161.4 K in R=Ho. The compounds with an incommensurate CDW exhibit a second transition at with between 55 K in R=Er and 111.5 K in R=Tm. In and this is a pure lock-in transition at which becomes zero. In and also becomes zero, but below additional satellite reflections have been discovered, at commensurate positions in and at incommensurate positions with in The development of this second CDW can be understood by a two-step mechanism similar to the mechanism for the development of the primary CDW in [Galli et al., Phys. Rev. Lett. 85, 158 (2000)]. At the primary CDW becomes commensurate, leading to a partly restoration of the Fermi surface, as evidenced by an anomalous decrease of the electrical resistivity for T below in and The modified Fermi surface then provides the favorable nesting conditions for the development of a second CDW in and The electronic character of this transition is suggested by the anomalous increase of the resistivity for T below
- Received 7 October 2003
DOI:https://doi.org/10.1103/PhysRevB.69.014103
©2004 American Physical Society