Tomonaga-Luttinger parameters for doped Mott insulators

• DOI: 10.1209/epl/i2005-10020-8
• Publication Date: 2005-04-14T12:45:49Z
• Authors: S Ejima; F Gebhard; S Nishimoto
• Keywords: Mott insulator

The Tomonaga--Luttinger parameter $K_{\rho}$ determines the critical behavior in quasi one-dimensional correlated electron systems, e.g., exponent $\alpha$ for density of states near Fermi energy. We use numerical density-matrix renormalization group method to calculate from slope density-density correlation function momentum space at zero wave vector. check accuracy our new approach against exact results Hubbard and XXZ Heisenberg models. determine phase diagram extended model quarter filling, $n_{\rm c}=1/2$, confirm bosonization $K_{\rho}=n_{\rm c}^2=1/4$ on line $K_{\rho}^{\rm CDW}=n_{\rm c}^2/2=1/8$ infinitesimal doping charge-density-wave (CDW) insulator all interaction strengths. doped CDW exhibits exponents $\alpha>1$ only small strong correlations.