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New type of antiferromagnetic polaron and bipolaron in HTc - superconductors

E. Hankiewicz·R. Buczko·Z. Wilamowski
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Abstract

The possibility of formation of a new type of polaron based on the quantum aniferromagnet (AF) model is reported. We take into account exchange interactions between localized d-d spins of the AF, as well as the p-d interaction of the AF with p-carriers. The energy minimum is found when maximum charge density occurs on every second spin. The formation of such ``comb''-like polarons results from the damping of quantum fluctuations and the appearance of Van Vleck-like staggered magnetization. Such polarons tend to form pairs coupled by an AF ``glue''.

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E. Hankiewicz, R. Buczko, Z. Wilamowski. 1999-07-06. New type of antiferromagnetic polaron and bipolaron in HTc - superconductors. https://doi.org/10.1016/s0921-4526(99)02005-0

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