Charge-density waves arising from two electron bands

D. W. Buker
2010 Proceedings of the Royal Society A  
A theory for a quasi-one-dimensional incommensurate charge-density wave state arising from electron-phonon (el-phon) interaction connecting electron states in two different bands is presented. An expression for the fundamental component of the energy gap as a function of the effective el-phon coupling, valid for all coupling strengths, has been found. For a single band, the expression simplifies to a reciprocal hyperbolicsine dependence on the reciprocal effective coupling. The effective
more » ... g, although simply related to the n assumed phonon-band frequencies, is not generally expressible as a sum of independent functions of these frequencies. The theory is applied to tetrathiofulvalinium-tetracyanoquinodimethane and to potassium blue bronze. 0 ()de, where D is the density of states at the Fermi level and E c is the cutoff.
doi:10.1098/rspa.2010.0085 fatcat:iufj7iwv5vazlid7jmcfsgp43e