N\'eel and disordered phases of coupled Heisenberg chains

We use the recently proposed two-step density-matrix renormalization group method to study the effects of frustration in Heisenberg models with S=$\frac{1}{2}$ to S=4 in a two- dimensional spatially anisotropic lattice. We find that the system is made of nearly disconnected chains at the maximally frustrated point, $J_d/J_{\perp}=0.5$, i.e., the transverse spin-spin correlations decay exponentially. This leads to the following consequences: (i) all half-integer spins systems are gapless, behaving like a sliding Luttinger liquid; (ii) for integer spins, there is an intermediate disordered phase with a spin gap, with the width of the disordered state is roughly proportional to the 1D Haldane gap.