Physical review. B, Condensed matter
Critical exponents of the SU(N) multicomponent Hubbard model and supersymmetrict-Jmodel in one dimension
Norio Kawakami
Abstract
Using conformal field theory the exact critical exponents are obtained for the SU(N) generalization of the U\ensuremath{\rightarrow}\ensuremath{\infty} Hubbard model and the supersymmetric t-J model in one dimension. For the Hubbard model the critical exponent of the momentum distribution function is given as \ensuremath{\theta}=(1-1/N${)}^{2}$/2 while for the supersymmetric t-J model \ensuremath{\theta} varies continuously in the range 0\ensuremath{\le}\ensuremath{\theta}\ensuremath{\le}(1-1/N${)}^{2}$/2 depending on the electron concentration. The critical exponents of various correlation functions are shown to satisfy the universal scaling relations. The SU(N) t-J model in the range 0J/t\ensuremath{\le}2 belongs to the SU(N) Luttinger liquid for any finite N.