Treating the hole-magnon interaction within the self-consistent Born approximation, we demonstrate that the low-energy quasiparticles that occur in the t-J model due to quantum 6uctuations of the spin system survive in the models including free hole propagation on the sublattices. The quasiparticle dispersion and weight are found to be strongly dependent on the next-neighbor hopping parameter. The Hat band observed near the X point in the high-temperature superconductors is reproduced, but not for the realistic parameters that correspond to the hole-doped system.

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We study the one hole spectral function in a model for LaMnO3 including both the effects of orbital ordering and the quantum decoherence due to the antiferromagnetic coupling between the ferromagnetic layers. We find that the classical picture of a ferromagnetic polaron does not apply and free dispersion is replaced by rigid quasiparticles on the scale of magnetic excitations, while the spectra are dominated by the incoherent spectral weight at high energies. These results have important implications on the in-plane transport and angular resolved photoemission in the manganites.