Single hole motion in LaMnO₃

We study single hole motion in LaMnO$_3$ using the classical approximation for JT lattice distortions, a modified Lang-Firsov approximation for dynamical breathing-mode phonons, and the self-consistent Born approximation (verified by exact diagonalization) for hole-orbital-excitation scattering. We show that in the realistic parameter space for LaMnO$_3$, quantum effects of electron-phonon interaction are small. The quasiparticle bandwidth $W \simeq 2.2J$ in the purely orbital t-J model. It is strikingly broadened to be of order $t$ by strong static Jahn-Teller lattice distortions even when the polaronic band narrowing is taken into account.