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Charge ordering and spin dynamics in NaV(2)O(5)
B Grenier1, O Cepas, L P Regnault
1Département de Recherche Fondamentale sur la Matière Condensée, SPSMS, Laboratoire de Magnétisme et de Diffraction Neutronique, CEA-Grenoble, F-38054 Grenoble cedex 9, France.
Physical Review Letters
|June 21, 2001
Summary
High-resolution neutron scattering reveals spin excitation gaps in NaV(2)O(5) below T(c). These gaps are linked to charge transfer and a precise zigzag charge distribution on the ladder rungs.
Area of Science:
- Condensed matter physics
- Materials science
- Quantum magnetism
Background:
- Sodium vanadate (NaV(2)O(5)) exhibits complex magnetic and electronic properties.
- Understanding spin excitations is crucial for characterizing its low-temperature phases.
Purpose of the Study:
- To investigate the spin excitations in NaV(2)O(5) using high-resolution neutron inelastic scattering.
- To determine the charge distribution and its relation to observed spin gaps.
Main Methods:
- High-resolution neutron inelastic scattering experiments.
- Analysis of spin excitation modes, dispersion, and intensity.
Main Results:
- Identification of two distinct energy branches with energy gaps below the critical temperature (T(c)).
- Deduction of a precise zigzag charge distribution on the ladder rungs.
- Determination of a charge order parameter Delta(c) approximately 0.6.
Conclusions:
- The observed spin gaps in the low-temperature phase are primarily attributed to charge transfer.
- The findings elucidate the interplay between charge order and spin dynamics in NaV(2)O(5).
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