Abstract
Incommensurate spin-density waves (ISDW) in Cr and its alloys are studied based on the two-band imperfect-nesting model with linearized dispersions within the mean-field approximation, considering infinite numbers of higher harmonics. An exact solution of the kink lattice is obtained and found to describe the SDW in Cr and its alloys. Two energy gaps observed optically are attributed to the midgap state associated with the kink lattice characteristic of the incommensurate structure.