Hcromagnetic method of s-parameter characterization of magnonic devices

摘要

Designers of nano-scale magnonic devices would benefit from methods of their evaluation that do not require one to access the microscopic level of description or to construct device prototypes. Here, we propose a numerical micromagnetics version of such a method, in which magnonic devices are considered as two-port linear networks and can therefore be described in terms of their s-parameters (i.e., reflection and transmission characteristics). In the micromagnetic model, the sample is composed from a magnonic device-under-test situated between input and output magnonic waveguides. First, dispersion relations and amplitudes of spin waves in the input and output waveguides are calculated from the simulations. The results are then compared to derive the s-parameters of the device-under-test. We use a simple rectangular magnetic nonuniformity, for which analytical results are readily obtained, to evaluate the efficiency and limitations of the technique in the sub-terahertz band.