arXiv:cond-mat/0101450 · Physical review. B, Condensed matter
Effect of nearest- and next-nearest neighbor interactions on the spin-wave velocity of one-dimensional quarter-filled spin-density-wave conductors
Yuh Tomio, N. Dupuis, Yoshikazu Suzumura
Abstract
We study spin fluctuations in quarter-filled one-dimensional spin-density-wave systems in presence of short-range Coulomb interactions. By applying a path integral method, the spin-wave velocity is calculated as a function of on-site $(U),$ nearest (V) and next-nearest ${(V}_{2})$ neighbor-site interactions. With increasing V or ${V}_{2},$ the pure spin-density-wave state evolves into a state with coexisting spin- and charge-density waves. The spin-wave velocity is reduced when several density waves coexist in the ground state, and may even vanish at large V. The effect of dimerization along the chain is also considered.