AN EXACTLY SOLVABLE FERMION MODEL: SPINONS, HOLONS AND A NON-FERMI LIQUID PHASE

Abstract

An interacting fermion model in d-dimensions is introduced and solved exactly. Low energy excitations have complete spin-charge decoupling. The holon spectrum is gapless and exhibits a pseudo-Fermi surface. Spinons have a gap and, as in the 1-D Hubbard model, the spinons exist only in a limited region of the Brillouin Zone. As a function of electron concentration the system exhibits metal insulator transition.