Effect of Lattice Quantum Fluctuation on CDW of MX Solids

摘要

The reduction of charge density wave (CDW) amplitude of MX solids caused by the lattice quantum fluctuation is investigated in a. wide range of electron-phonon coupling by using the self-consistent renormalization method, In contrast to polyacetylene, where the bond order wave (BOW) exists well in arbitrary coupling, tJie effect of the quantum fluctuation on CDW of MX solids distinctly depends on the coupling. When the coupling is strong, the reduction of CDW is small; but, if the coupling is weaJc, CDW is seriously suppressed and even nearly destroyed. This contrast is related to the fact that for weak coupling, the renormalized frequencies of both the acoustic and optical branches are greaiiy reduced j'ji polyacetylene, but these frequencies in MX solids are not well different from the bare vaiue.