High frequency ESR investigation on dynamical charge disproportionation and spin gap excitation in NaV_2O_5

Abstract

A significant frequency dependence of the ESR line width is found in NaV_2O_5 between 34-100 K and the line width increases as the resonance frequency is increased from 95 GHz to 760 GHz. The observed frequency dependence is qualitatively explained in terms of the dynamical charge disproportionation. The present results show the essential role of the internal charge degree of freedom in a V-O-V bond. We have also proposed the existence of the Dzyaloshinsky-Moriya interaction in the low temperature charge ordered phase considering the breaking of the selection rule of ESR realized as the direct observation of the spin gap excitation.

9 figures submitted to J. Phys.Soc. Jpn

References in corpus (7)

• Theory of Low Temperature Electron Spin Resonance in Half-integer Spin Antiferromagnetic Chains
• Direct observation of the multiple spin gap excitations in two-dimensional dimer system SrCu2(BO3)2
• ESR investigation on the Breather mode and the Spinon-Breather dynamical crossover in Cu Benzoate
• Submillimeter Wave ESR Study of Spin Gap Excitations in CuGeO3
• Optical spectroscopic study of the interplay of spin and charge in NaV2O5
• Electron-phonon and spin-phonon coupling in NaV${}_2$O${}_5$: charge fluctuations effect
• Theoretical study of the optical conductivity of ${\alpha }^{\prime }-Na{V}_2{O}_5$

Cited by in corpus (11)

• ESR study on the excited state energy spectrum of SrCu${}_2$(BO${}_3$)${}_2$ -a central role of multiple-triplet bound states
• Low energy excitations and dynamic Dzyaloshinskii-Moriya interaction in ${\alpha }^{\prime }$-NaV${}_2$O${}_5$ studied by far infrared spectroscopy
• Lattice vibrations of alpha'-NaV_2O_5 in the low-temperature phase. Magnetic bound states?
• Optical properties, electron-phonon coupling, and Raman scattering of vanadium ladder compounds
• Unconventional anisotropic superexchange in NaV2O5
• Theory of phonon-assisted "forbidden" optical transitions in spin-gapped systems
• Discussion of a spin-cluster model for the low temperature phase of NaV_2O_5
• Charge kinks as Raman scatterers in quarter-filled ladders
• Dzyaloshinskii-Moriya interaction in NaV${}_2$O${}_5$: a microscopic study
• Using electronic structure changes to map the H-T phase diagram of alpha'-NaV2O5
• Electronic Properties of α'-NaV_2O_5