Optical phonons for Peierls chains with long-range Coulomb interactions
arXiv:1611.04335 · doi:10.1103/PhysRevB.95.085150
Abstract
We consider a chain of atoms that are bound together by a harmonic force. Spin-1/2 electrons that move between neighboring chain sites (Hückel model) induce a lattice dimerization at half band filling (Peierls effect). We supplement the Hückel model with a local Hubbard interaction and a long-range Ohno potential, and calculate the average bond-length, dimerization, and optical phonon frequencies for finite straight and zig-zag chains using the density-matrix renormalization group (DMRG) method. We check our numerical approach against analytic results for the Hückel model. The Hubbard interaction mildly affects the average bond length but substantially enhances the dimerization and increases the optical phonon frequencies whereas, for moderate Coulomb parameters, the long-range Ohno interaction plays no role.
16 pages, 21 figures
References in corpus (5)
- The density-matrix renormalization group in the age of matrix product states
- Inelastic Light Scattering From Correlated Electrons
- Effect of Electron-Phonon Interaction Range for a Half-Filled Band in One Dimension
- Nature of ground states in one-dimensional electron-phonon Hubbard models at half-filling
- Phonon spectral function of the one-dimensional Holstein-Hubbard model