LAUSR

We theoretically and experimentally studied the Gilbert damping evolution of both acoustic and optical magnetic resonance modes in the layered flake CrCl3 with an external magnetic field H applied in plane. Based on a Lagrangian equation and a Rayleigh dissipation function, we predicted that the resonance linewidth ∆H as a function of microwave frequency ω is nonlinear for both acoustic and optical modes in the CrCl3 flake, which is significantly different from the linear relationship of ∆H ∝ ω in ferromagnets. By measuring the microwave transmission through the CrCl3 flake, we achieved the ω − H dispersion and damping evolution ∆H − ω for both acoustic and optical modes. Combining both our theoretical prediction and experimental observations, we concluded that the nonlinear damping evolution ∆H − ω is a consequence of the interlayer interaction during the antiferromagnetic resonance and the interlayer Gilbert dissipation plays an important role in the nonlinear damping evolution because of the asymmetry of the non-collinear magnetizaiton between layers.