Collective modes in the charge density wave state of K0.3MoO3 : Role of long-range Coulomb interactions revisited
Abstract
We re-examine the effect of long-range Coulomb interactions on the collective amplitude and phase modes in the incommensurate charge-density-wave ground state of quasi-one-dimensional conductors.Using an effective action approach we show that the longitudinal acoustic phonon protects the gapless linear dispersion of the lowest phase mode in the presence of long-range Coulomb interactions. Moreover, in Gaussian approximation, amplitude fluctuations are not affected by long-range Coulomb interactions. We also calculate the collective mode dispersions at finite temperatures and compare our results with the measured energies of amplitude and phase modes in K0.3MoO3 . With the exception of the lowest phase mode, the temperature dependence of the measured mode energies can be quantitatively described within a multiphonon Fröhlich model for generic electron-phonon interactions neglecting long-range Coulomb interactions.
- Publication:
-
Physical Review B
- Pub Date:
- July 2023
- DOI:
- 10.1103/PhysRevB.108.045148
- arXiv:
- arXiv:2303.08580
- Bibcode:
- 2023PhRvB.108d5148H
- Keywords:
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- Condensed Matter - Strongly Correlated Electrons
- E-Print:
- Phys. Rev. B 108, 045148 (2023)