Fermi surface nesting and charge-density wave formation in rare-earth   tritellurides
  The Fermi surface of rare-earth tri-tellurides ({\it R}Te$_{3}$) is investigated in terms of the nesting driven charge-density wave formation using positron annihilation and first-principles LMTO calculations. Fermi surface nesting is revealed as a strong candidate for driving charge-density wave formation in these compounds. The nesting vector obtained from positron annihilation experiments on GdTe$_{3}$ is determined to be ${\mathbf q} = (0.28\pm0.02,0,0) {\mathbf a}^{*}$, (${\mathbf a}^{*}=2\pi/{\mathbf a}$), in excellent agreement with previous experimental and theoretical studies. 
J.Laverock, S.B.Dugdale, Zs.Major, M.A.Alam, N.Ru, I.R.Fisher, G.Santi   and E.Bruno