Exact Solution of the Landau-Lifshitz Equation in a Plane Wave

The Landau–Lifshitz (The Classical Theory of Fields. Elsevier, Oxford 1975) form of the Lorentz–Abraham–Dirac equation in the presence of a plane wave of arbitrary shape and polarization is solved exactly and in closed form. The explicit solution is presented in the particular, paradigmatic cases of a constant crossed field and of a monochromatic wave with circular and with linear polarization.      

非线性“loop”孤子方程的确定解

提出一种求解非线性“loop”孤子方程确定解的新方法，即以“行波”为因子，利用幂级数直接求解该方程解析函数U(ξ)，用MatLab绘制c→光速和c→声速的U(ξ)-ξ图像，直 接观察该方程解的变化规律，找出该方程的确定解(含孤波解）. 该方法为求解难度大的非 线性孤子方程提供借鉴. 关键词： 非线性孤子方程 确定解 MatLab图像     

Gilbert damping in the layered antiferromagnet CrCl3

We theoretically and experimentally studied the Gilbert damping evolution of both acoustic and optical magnetic resonance modes in the layered flake Cr Cl;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 frequencyωis nonlinear for both acoustic and optical modes in the Cr Cl;flake,which is significantly different from the linear relationship of△H-ωin ferromagnets.Measuring the microwave transmission through the Cr Cl;flake,we obtained theω–H dispersion and damping evolution△H–ωfor both acoustic and optical modes.Combining both our theoretical prediction and experimental observations,we concluded that the nonlinear damping evolution△H–ωis 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.