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Magnetic and lattice polaron in Holstein-t-J model

E. Cappelluti·S. Ciuchi
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Abstract

We investigate the interplay between the formation of lattice and magnetic polaron in the case of a single hole in the antiferromagnetic background. We present an exact analytical solution of the Holstein-t-J model in infinite dimensions. Ground state energy, electron-lattice correlation function, spin bag dimension as well as spectral properties are calculated. The magnetic and hole-lattice correlations sustain each other, i.e. the presence of antiferromagnetic correlations favors the formation of the lattice polaron at lower value of the electron-phonon coupling while the polaronic effect contributes to reduce the number of spin defects in the antiferromagnetic background. The crossover towards a spin-lattice small polaron region of the phase diagram becomes a discontinuous transition in the adiabatic limit.

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E. Cappelluti, S. Ciuchi. 2002-06-11. Magnetic and lattice polaron in Holstein-t-J model. https://doi.org/10.1103/physrevb.66.165102

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