中国物理B ›› 2001, Vol. 10 ›› Issue (5): 384-389.doi: 10.1088/1009-1963/10/5/304
孙磊, 章豫梅, 冯伟国
Sun Lei (孙磊), Zhang Yu-mei (章豫梅), Feng Wei-guo (冯伟国)
摘要: The variational approach is applied to the study on the effect of Coulomb interaction between electrons on the dimerization in a one-dimensional commensurability-two Peierls system, such as trans-polyacetylene. For the case of omitting direct repulsion between electrons in the bonds between sites W, it is confirmed that the weak interactions tend to enhance the dimerization; but when W is included, this enhancement will be attenuated. If |W| is sufficiently large, the net effect of electron-electron interactions will reduce the magnitude of the electron-phonon-induced dimerization.
中图分类号: (Lattice fermion models (Hubbard model, etc.))