LOW-ENERGY AND HIGH-ENERGY EXCITATIONS IN THE INCOMMENSURATE ANTIFERROMAGNET, CHROMIUM

Dynamical susceptibility of metallic chromium (Cr) has been elucidated by using neutron magnetic scattering technique. Systematic studies in a wide energy range at various temperatures revealed that magnetic ex citations in the antiferromagnetic state of Cr well below Neel tempera ture are not interpreted by a simple spin-wave mode like in the conven tionally ordered magnet. The most prominent feature of spin dynamics i n the incommensurate spin density wave (SDW) state is that magnetic ex citations consist of two components having incommensurate and commensu rate wave vector in the reciprocal space. Energy and temperature depen dence of such magnetic excitations is also unusual, which may reflect the characteristic band structure of Cr. (C) 1998 Elsevier Science B.V . All rights reserved.