Topological bands in metals with helical magnetic order

The effect of a helicoidal magnetic field on the dispersion conduction electrons in one- and two-dimensional systems is investigated. In periodic field, there special symmetry with respect to reversal time, which leads peculiarities band structure. Using an example one-dimensional model system, topological properties structure effective corresponding 120 o -ordering are PdCrO 2 , ordering dielectric layers CrO creates unusual spin Fermi surface conducting palladium layers. this case, umklapp scattering mobile charge carriers strongly suppressed, abnormally high conductivity at low temperatures observed experimentally. Keywords: Helicoidal ordering, Time-reversal symmetry, Band structure, Charge scattering, Metallic delafossites, 3 .