Diode Effect in the Medium with a Helical Magnetic Structure
  The volt-ampere characteristics of a medium with helical magnetic structure are theoretically studied. Phenomenological and microscopic theories of a diode effect in such a medium are proposed. Diode effect appears only in the medium with noncoplanar magnetic structure. Two mechanisms for the diode effect are considered. They are electron energy spectrum asymmetry and electron scattering asymmetry. 
A.A. Fraerman, O.G. Udalov