A helimagnet is a chiral magnet in which the direction of the magnetic moment spatially rotates in a plane perpendicular to the propagation vector. The sense of the rotation known as spin helicity is a robust degree of freedom of matter and 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 magnetic fields and electric currents in an itinerant helimagnet MnP. Second-harmonic resistivity measurements allow us to read out the controlled helicity. In contract to an insulating multiferroic magnet, in which spin rotation was shown to be controllable by an electric field, we achieve helicity manipulation by using an electric current in the conducting helimagnet. The controllability of the spin helicity may pave the way to new method of realizing magnetic memories based on the spin internal degrees of freedom.

螺旋磁铁是一种手性磁铁，其中磁矩的方向在垂直于传播矢量的平面中空间旋转。称为自旋螺旋度的旋转感是一种可靠的物质自由度，如果可以电气控制和检测，则可以提供磁存储器的新概念。在这里，我们显示了螺旋度可以通过磁场和流动的电磁磁铁MnP中的电流来控制。次谐波电阻率测量值使我们可以读出受控的螺旋度。与绝缘多铁磁体（其中自旋旋转可通过电场控制）相比，我们通过在导电直升机中使用电流来实现螺旋度操纵。