TRANSPORT THROUGH A 1D MOTT-HUBBARD INSULATOR OF FINITE-LENGTH

Transport through a 1D Mott-Hubbard insulator of a finite length L is studied beyond the perturbative approach. At a special value of the lo w-energy constant of the interaction we have mapped the problem onto e xactly solvable models and found current vs voltage at a high temperat ure T > max(m, T-L) and at a low energy T, V < T-L (T-L = v(c)/L: char ge velocity). The result shows that for the strong interaction creatin g a large Mott-Hubbard gap 2m >> T-L inside the wire, the transport is suppressed near half filling everywhere inside the gap except for a s mall region where V, T < T-L exp(-2m/T-L).