Spin-phase detection by spin current in a chiral helimagnet

The authors demonstrate here electrical detection of the spin phase in a van der Waals chiral helimagnet CrNb₃S₆ using a nonlocal spin valve. Because the spin diffusion length of the helimagnet (~5 nm) is much shorter than the helical pitch (48 nm), spin current sensitively probes the surface magnetic moment. Moreover, inverse spin Hall measurements reveal enhanced spin fluctuations near TC. These findings clearly indicate that the present method is highly effective for detecting surface magnetization and spin dynamics in low-dimensional systems.