TY - JOUR

T1 - Charge order induced by electron-lattice interaction in Na V2 O5

AU - Edegger, B.

AU - Evertz, H.G.

AU - Noack, R.M.

PY - 2005

Y1 - 2005

N2 - We present density matrix renormalization group calculations of the ground-state properties of quarter-filled ladders including static electron-lattice coupling. Isolated ladders and two coupled ladders are considered, with model parameters obtained from band-structure calculations for α′−NaV2O5. The relevant Holstein coupling to the lattice causes static out-of-plane lattice distortions, which appear concurrently with a charge-ordered state and which exhibit the same zigzag pattern observed in experiments. The inclusion of electron-lattice coupling drastically reduces the critical nearest-neighbor Coulomb repulsion Vc needed to obtain the charge-ordered state. No spin gap is present in the ordered phase. The charge ordering is driven by the Coulomb repulsion and the electron-lattice interaction. With electron-lattice interaction, coupling two ladders has virtually no effect on Vc or on the characteristics of the charge-ordered phase. At V=0.46eV, a value consistent with previous estimates, the lattice distortion, charge gap, charge-order parameter, and the effective spin coupling are in good agreement with experimental data for NaV2O5.

AB - We present density matrix renormalization group calculations of the ground-state properties of quarter-filled ladders including static electron-lattice coupling. Isolated ladders and two coupled ladders are considered, with model parameters obtained from band-structure calculations for α′−NaV2O5. The relevant Holstein coupling to the lattice causes static out-of-plane lattice distortions, which appear concurrently with a charge-ordered state and which exhibit the same zigzag pattern observed in experiments. The inclusion of electron-lattice coupling drastically reduces the critical nearest-neighbor Coulomb repulsion Vc needed to obtain the charge-ordered state. No spin gap is present in the ordered phase. The charge ordering is driven by the Coulomb repulsion and the electron-lattice interaction. With electron-lattice interaction, coupling two ladders has virtually no effect on Vc or on the characteristics of the charge-ordered phase. At V=0.46eV, a value consistent with previous estimates, the lattice distortion, charge gap, charge-order parameter, and the effective spin coupling are in good agreement with experimental data for NaV2O5.

UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-33644952787&partnerID=MN8TOARS

U2 - 10.1103/PhysRevB.72.085131

DO - 10.1103/PhysRevB.72.085131

M3 - Article

VL - 72

JO - Physical Review B

JF - Physical Review B

SN - 1098-0121

IS - 8

M1 - 085131

ER -