Spin Liquid State around a Doped Hole in Insulating Cuprates

Abstract
The numerically exact diagonalization study on small clusters of the t - J model with second- and third-neighbor hopping terms shows that a novel spin liquid state is realized around a doped hole with momentum k =(π, 0) and energy ∼2 J compared with that with (π/2, π/2) in insulating cuprates, where the spin and charge degrees of freedom are approximately decoupled. Our finding implies that the excitations in the insulating cuprates are mapped onto the d -wave resonating valence bond state.