Effect of collective spin excitations on electronic transport in topological spin textures

In recent years, the anomalous transverse conduction due to the topology in the real space has attracted much attention. It is known that the local spins can have the noncoplanar structure in the triangular lattice systems, and it has been reported both experimentally and theoretically that they exhibit the topological Hall effects.[1][2] In addition, the influence of the collective excitations of the spin systems on the response of electronic systems has recently been discussed by calculating the real-time evolution of the charge-spin systems.[3]

In this study, [4] we focus on the effect of the collective excitation of the localized spins on the electronic transport properties of the non-trivial topological state in real space. To investigate this effect, we calculate the linear optical conductivity by calculating the real-time evolution of the Kondo lattice model on the triangular lattice, which hosts an all-in/all-out magnetic structure. In the linear conductivity spectra, we observe multiple peaks below the bandgap regime, attributed to the resonant contributions of collective modes similar to the skyrmionic system. We elucidate the interference between the contributions from the different spin excitations to the optical conductivity in the multiple spin texture, pointing out the mode-dependent electrical activity. We show the complex interplay between the complex spin texture and the itinerant electrons in the twodimensional spin-charge coupled system.