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On the stability of polaronic superlattices in strongly coupled electron-phonon systems

G. Wellein·H. Fehske·H. Büttner·A. R. Bishop
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Abstract

We investigate the interplay of electron-phonon (EP) coupling and strong electronic correlations in the frame of the two-dimensional (2D) Holstein t-J model (HtJM), focusing on polaronic ordering phenomena for the quarter-filled band case. The use of direct Lanczos diagonalization on finite lattices allows us to include the effects of quantum phonon fluctuations in the calculation of spin/charge structure factors and hole-phonon correlation functions. In the adiabatic strong coupling regime we found evidence for ``self-localization'' of polaronic carriers in a $(π,π)$ charge-modulated structure, a type of superlattice solidification reminiscent of those observed in the nickel perovskites $La_{2-x}Sr_{x}NiO_{4+y}$.

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G. Wellein, H. Fehske, H. Büttner, A. R. Bishop. 1996-12-23. On the stability of polaronic superlattices in strongly coupled electron-phonon systems. https://doi.org/10.1016/s0921-4534(97)01042-3

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