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Competition of Dimerization and Charge Ordering in the Spin-Peierls State of Organic Conductors

Muneo Sugiura·Yoshikazu Suzumura
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Abstract

The effect of the charge ordering on the spin-Peierls (SP) state has been examined by using a Peierls-Hubbard model at quarter-filling with dimerization, on-site and nearest-neighbor repulsive interactions. By taking account of the presence of dimerization, a bond distortion is calculated variationally with the renormalization group method based on bosonization. When the charge ordering appears at V=V_c with increasing the nearest-neighbor interaction (V), the distortion exhibits a maximum due to competition between the dimerization and the charge ordering. It is shown that the second-order phase transition occurs from the SP state with the bond alternation to a mixed state with an additional component of the site alternationat V = V_c.

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Muneo Sugiura, Yoshikazu Suzumura. 2003-03-25. Competition of Dimerization and Charge Ordering in the Spin-Peierls State of Organic Conductors. https://doi.org/10.1143/jpsj.72.1458

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