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Co-operative density wave and giant spin gap in the quarter-filled zigzag ladder

R. T. Clay·S. Mazumdar
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Abstract

Strong co-operative interactions occur between four different broken symmetries involving charge-ordering and bond distortions in the quarter-filled correlated zigzag electron ladder. The ground state is singlet, with spin gap several times larger than in the spin-Peierls state of the one-dimensional quarter-filled chain with the same parameters. We propose the quarter-filled zigzag electron ladder model for several different organic charge-transfer solids with coupled pairs of quasi-one-dimensional stacks, the spin-gap transition temperatures in which are unusually high.

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R. T. Clay, S. Mazumdar. 2005-04-21. Co-operative density wave and giant spin gap in the quarter-filled zigzag ladder. https://doi.org/10.1103/physrevlett.94.207206

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