Charge ordering and opening of spin gap in NaV_2O_5

Abstract

We suggest that the phase transition observed in NaV_2O_5 at T_c = 34K is not a spin-Peierls transition, but a charge ordering transition, related to the formal presence in this system of equal number of V^4+ and V^4- ions. Below T_c, V^4+ ions form a zigzag structure, which is consistent with the experimentally observed doubling of the lattice period in a and b directions. We show that this charge ordering also results in the alternation of spin exchange constants along the b-direction, which opens a gap in the spin excitation spectrum. We emphasize the role of lattice distortions around V ions both in the formation of the charged ordered state and in the spin-gap opening.

5 pages, revtex, epsf, 3 Postscript figures

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Cited by in corpus (42)

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• Zigzag Charge Ordering in alpha'-NaV2O5
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• Spectrum and correlation functions of a quasi-one-dimensional quantum Ising model
• Lattice vibrations of alpha'-NaV_2O_5 in the low-temperature phase. Magnetic bound states?
• Nature of insulating state in NaV${}_2$O${}_5$ above charge-ordering transition: a cluster DMFT study
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• Low-energy excitations in NaV2O5
• Ordering in Two-Dimensional Ising Models with Competing Interactions
• Investigation of thermal and magnetic properties of defects in a spin-gap compound NaV2O5
• Charge ordering in quarter-filled ladder systems coupled to the lattice
• Superexchange in the quarter- filled two- leg ladder system NaV2O5
• Single-particle spectral function of quarter-filled ladder systems
• Simultaneous Charge Ordering and Spin Dimerization in Quasi-Two-Dimensional Quarter-Filled Ladders
• Can a frustrated spin-cluster model describe the low-temperature physics of NaV_2O_5 ?
• Charge excitations in NaV${}_2$O${}_5$
• Mixed spin S=1 and S=1/2 layered lattice in Cu${}_2$F${}_5$
• Discussion of a spin-cluster model for the low temperature phase of NaV_2O_5
• Electron spin resonance study of Na_{1-x}Li_xV_2O_5
• Creation and destruction of a spin gap in weakly coupled quarter-filled ladders
• Charge kinks as Raman scatterers in quarter-filled ladders
• Near degeneracy and pseudo Jahn-Teller effects in mixed-valence ladders: the phase transition in NaV${}_2$O${}_5$
• Magnetic properties of a spin-1/2 quadrumer chain
• Spin and charge excitations in the anisotropic Hubbard ladder at quarter filling with charge-ordering instability
• Charge order induced by electron-lattice interaction in NaV2O5
• Ground state and finite temperature behavior of 1/4-filled band zigzag ladders
• The excitations of the sympletic integrable models and their applications
• Using electronic structure changes to map the H-T phase diagram of alpha'-NaV2O5
• The Spin-SAF transition in NaV2O5 induced by spin-pseudospin coupling
• Dynamical Properties of One-Dimensional Multicomponent Quantum Liquids in Metallic Phase
• Electronic Properties of α'-NaV_2O_5
• Dimerization-induced enhancement of the spin gap in the quarter-filled two-leg rectangular ladder
• From frustrated insulators to correlated anisotropic metals: charge ordering and quantum criticality in coupled chain systems