Falcão P R N, Lyra M L
Instituto de Física, Universidade Federal de Alagoas, 57072-900, Maceió-AL, Brazil.
J Phys Condens Matter. 2021 Jun 23;33(32). doi: 10.1088/1361-648X/ac05e6.
We investigate the asymmetric wave scattering in a phononic one-dimensional lattice with a nonreciprocal defect and position dependent masses coupled by the defect spring. The nonreciprocal interaction is characterized by a single parameter Δ while the nonlinear contribution due to position-dependent masses are controlled by a parameter. The transmission and reflection coefficients are analytically computed and the effects of the nonreciprocity and nonlinearity are detailed. We show that, in opposite with the linear case, the rectification factor has a frequency dependence, which leads to a more efficient diode-like action at large wavevectors. Further, the nonlinearity leads to an asymmetry of the reflected component, absent in the linear regime. We extend our analysis to a system with frictional forces which suppresses the multistability window promoted by the nonlinear mass contribution without compromising the rectification action.
我们研究了具有非互易缺陷以及由缺陷弹簧耦合的位置依赖质量的一维声子晶格中的非对称波散射。非互易相互作用由单个参数Δ表征，而位置依赖质量引起的非线性贡献由一个参数控制。通过解析计算得到了透射和反射系数，并详细研究了非互易性和非线性的影响。我们表明，与线性情况相反，整流因子具有频率依赖性，这导致在大波矢处具有更高效的类二极管作用。此外，非线性导致反射分量的不对称性，这在线性 regime 中不存在。我们将分析扩展到具有摩擦力的系统，该系统抑制了由非线性质量贡献促进的多稳态窗口，而不会损害整流作用。
