Electrical Detection of Spin Dynamics in Chiral Helimagnet Cr_1/3NbS₂

Chiral materials can host a variety of topological spin textures with the potential for computational applications. Giant topological Hall effect and formation of chiral soliton lattice in Cr-intercalated NbS₂ (Cr_1/3NbS₂) have attracted significant interest to this material. However, its spin dynamics have remained largerly unexplored. Here, we report microwave spectroscopy at low temperatures and show how spin waves can be used as a probe for the magnetic structure. We observe transition of the chiral-state spin wave mode into the forced-ferromagnet spin wave mode with applying magnetic field along the c-axis. With increasing temperature, the forced-ferromagnet spin wave mode undergoes an abrupt frequency shift, signifying a phase transition of the underlying spin order into the paramagnetic state. We furthermore succeed in detecting the magnon modes using longitudinal and transverse magnetoresistance of Cr_1/3NbS₂. This technique is the prerequisite for minituarization of the magnetic elements and thus paves the road toward functionalization of this chiral magnetic material in magnetoelectronic devices.