Electric current control of spin helicity in an itinerant helimagnet

The mechanism of homochirality in biological objects and other materials has been attracting great attention. The longitudinal helical magnetic structure is the chiral magnetic object, in which the ordered direction of the magnetic moment spatially rotates in the plane perpendicular to the propagation vector and the sense of rotation denoted as helicity determines the chirality. The robust magnetic degree of freedom may provide a new concept of magnetic memory if it can be electrically controlled and detected. Here we show that the helicity can be controlled by the magnetic field and electric current, and probed by the second-harmonic resistivity, which is sensitive to the chiral symmetry breaking, in an itinerant longitudinal helimagnet MnP. While the helicity can be controlled by the electric field in insulating multiferroic helimagnets, we have achieved the helicity manipulation in the conducting helimagnet compatible with electric circuits. The controllability may pave a new route to the spintronics.