Loughborough University
9511116.pdf (400.38 kB)

Spin density wave selection in the one-dimensional Hubbard model

Download (400.38 kB)
posted on 2006-04-05, 16:50 authored by John Samson
The Hartree-Fock ground state phase diagram of the one-dimensional Hubbard model is calculated, constrained to uniform phases, which have no charge density modulation. The allowed solutions are saturated ferromagnetism (FM), a spiral spin density wave (SSDW) and a double spin density wave} (DSDW). The DSDW phase comprises two canted interpenetrating antiferromagnetic sublattices. FM occurs for small filling, SSDW in most of the remainder of the phase diagram, and DSDW in a narrow tongue near quarter (and three-quarter) filling. Itinerant electrons lift the degeneracy with respect to canting angle in the DSDW. The Hartree-Fock states are metallic except at multiples of a quarter filling. Near half filling the uniform SSDW phase is unstable against phase separation into a half-filled antiferromagnetic phase and a hole-rich SSDW phase. The dependence of the ground state wave number on chemical potential is conjectured to be a staircase. Comparison is made with higher dimensional Hubbard models and the $J_{1}-J_{2}$ Heisenberg model.



  • Science


  • Physics


409993 bytes

Publication date



This is a pre-print. It is also available at: http://arxiv.org/abs/cond-mat/9511116. The definitive version: SAMSON, 1996. Spin density wave selection in the one-dimensional Hubbard model. Journal of Physics: Condensed Matter, 8(5), pp. 569-580, is available at: http://www.iop.org/EJ/journal/JPhysCM.


  • en