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Electron-phonon coupling and spin-charge separation in one-dimensional Mott insulators

Hiroaki Matsueda·Takami Tohyama·Sadamichi Maekawa
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Abstract

We examine the single-particle excitation spectrum in the one-dimensional Hubbard-Holstein model at half-filling by performing the dynamical density matrix renormalization group (DDMRG) calculation. The DDMRG results are interpreted as superposition of spectra for a spinless carrier dressed with phonons. The superposition is a consequence of robustness of the spin-charge separation against electron-phonon coupling. The separation is in contrast to the coupling between phonon and spin degrees of freedom in two-dimensional systems. We discuss implication of the results of the recent angle-resolved photoemission spectroscopy measurements on SrCuO${}_{2}$.

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Hiroaki Matsueda, Takami Tohyama, Sadamichi Maekawa. 2005-11-03. Electron-phonon coupling and spin-charge separation in one-dimensional Mott insulators. https://doi.org/10.1103/physrevb.74.241103

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