DYNAMICAL RESPONSE FUNCTION OF 2K(F)-SDW FOR THE TOMONAGA-LUTTINGER MODEL

The response function, chi(SDW)(R)(q, omega), Of 2k(F)-SDW (spin densi ty wave) with momentum 2k(F) + q and frequency omega has been studied for the Tomonaga-Luttinger model by taking account of the momentum cut off of the repulsive interaction where k(F) is the Fermi momentum. We have found that Im chi(SDW)(R)(q,omega) as a function of omega exhibit s a novel peak located at an energy with the Fermi velocity in additio n to two peaks at energies with the renormalized velocities, v(rho) an d v(sigma) corresponding to charge and spin excitations. Temperature d ependence of Im chi(SDW)(R)(q, omega) is calculated to show that the s pin fluctuation is dominant at low temperatures for the strong interac tion and that the peak vanishes at high temperatures leading to a cros sover into that in the absence of interaction.