Charge fluctuations in a system of spin density waves

Abstract

We have studied charge fluctuations in a system of spin density waves. We show that in the long wavelength regime, along with modified Langmuir vibrations there exists a branch of the zero-sound type. At wave vectors close to the wave vector of the spin density wave, there are two activation branches of charge fluctuations with activation energies of the order of the gap width in the spectrum of the single-particle spin density wave excitations.