Exact charge dynamics in the supersymmetric t-J model with inverse-square interaction

The dynamical charge structure factor N(Q,omega) with Q smaller than the Fe rmi wave number is derived analytically for the one-dimensional supersymmet ric t-J model with 1/r(2) interaction. Strong spin-charge separation in dyn amics is found. N(Q,omega) which a given electron density does not depend o n the spin polarization of a system with an arbitrary size, In the thermody namic limit, only two holons and one antiholon contribute to N(Q,omega). Th ese results together with generalized ones for the SU(K,1) supersymmetric t -J model are derived via solution of the Sutherland model in the strong cou pling limit.