Anomalous Scaling and Spin-Charge Separation in Coupled Chains

We use a bosonization approach to show that the three-dimensional Coulomb interaction in coupled metallic chains leads to a Luttinger liquid for vanishing interchain hopping $t_{\perp }$, and to a Fermi liquid for any finite $t_{\perp }$. However, for small $t_{\perp }\ne 0$ the Green's function satisfies a homogeneity relation with a nontrivial exponent ${\gamma }_{\mathrm{cb}}$ in a large intermediate regime. Our results offer a simple explanation for the large values of ${\gamma }_{\mathrm{cb}}$ inferred from recent photoemission data from quasi-one-dimensional conductors and might have some relevance for the understanding of the unusual properties of the high-temperature superconductors.