Peierls - density modulation of ion background break down...

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Phonons Phonons in metals - Kohn in metals - Kohn anomaly anomaly ion background oscillation relative to (fixed) electron analog to plasma oscillation ion mass ion density ion charge screening of Coulomb by (fast) electrons sound velocity Kohn anomaly singular at 2k F
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Peierls instability Peierls instability in 1D in 1D metal metal (Jellium model) electron kinetic energy elastic energy deformation along x electron-phonon coupling screened Coulomb (short range) ion-electron ion density fluctuation electron density
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Peierls instability Peierls instability in 1D in 1D metal metal (Jellium model) phonon dispersion electron-phonon coupling as perturbation Fourier:
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Peierls instability Peierls instability in 1D in 1D metal metal 2 nd -order Rayleigh-Schrödinger perturbation essentially no q-dependence screening correction to phonon dispersion Lindhard function
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Peierls instability Peierls instability in 1D in 1D metal metal instability Bose-Einstein condensation of coherent phonons
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Unformatted text preview: density modulation of ion background break down of perturbation theory periodically modulated (weak) ion potential case for nearly free electron approximation Peierls instability Peierls instability in 1D in 1D metal metal nearly free electron approximation secular equation occupied empty total ground state energy elastic expense electronic gain Peierls instability Peierls instability in 1D in 1D metal metal elastic expense electronic gain minimize w.r.t. density of states at Fermi energy electron-phonon coupling constant energy gap of insulating phase Peierls instability instability of Fermi surface Peierls instability Peierls instability in 1D in 1D metal metal charge modulation of electrons and ions electron wave function (NFEA) Charge Density Wave experimental systems TTF-TCNQ resistivity metal-insulator transition NbSe 3 STM charge density modulation organic conductor H. Alves et al. Nature Materials S. Yasuzuka et al. JPSJ(2007)...
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Peierls - density modulation of ion background break down...

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