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arXiv · 0801.1889

Possible Metastable State Triggered by Competition of Peierls State and Charge Ordered State

Y. Omori·M. Tsuchiizu·Y. Suzumura
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Abstract

We examine a Peierls ground state and its competing metastable state in the one-dimensional quarter-filled Peierls-Hubbard model with the nearest-neighbor repulsive interaction V and the electron-phonon interaction (\propto 1/K with K being the elastic constant). From the mean-field approach, we obtain the phase diagram for the ground state on the plane of parameters V and K. The coexistent state of the spin-density wave and the charge ordering is realized for large V and K. With decreasing K, it exhibits a first-order phase transition to the unconventional Peierls state which is described by the bond-centered charge-density-wave state. In the large region of the Peierls ground state in the phase diagram, there exists the metastable state where the energy takes a local minimum with respect to the lattice distortion. On the basis of the present calculation, we discuss the photoinduced phase observed in the (EDO-TTF)_{2}PF_{6} compound.

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Y. Omori, M. Tsuchiizu, Y. Suzumura. 2008-01-12. Possible Metastable State Triggered by Competition of Peierls State and Charge Ordered State. https://doi.org/10.1143/jpsj.76.114709

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