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Role of the superexchange interaction in magnetic transition and polaron crossover

Jayita Chatterjee·A. N. Das
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Abstract

The Hubbard-Holstein model is studied including double-exchange interaction and superexchange interaction using a variational phonon basis obtained through the modified Lang-Firsov (MLF) transformation followed by the squeezing transformation. The kinetic energy, polaron crossover and magnetic transition are investigated as a function of electron-phonon ($e$-ph) coupling and electron concentration for different values of antiferromagnetic superexchange interaction ($J$) between the core spins. The polaron crossover, magnetic transition and the suppression of ferromagnetic transition with $J $ are discussed for the model.

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Jayita Chatterjee, A. N. Das. 2003-12-03. Role of the superexchange interaction in magnetic transition and polaron crossover. https://doi.org/10.1016/j.physb.2003.11.075

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