Spin-Wave Linewidth Measurement of Microwave Gyromagnetic Materials in a Low RF Power

In this paper, a novel test system for spin-wave linewidth has been proposed. As the traditional test system requires a high-power RF source, a high Q cylindrical resonator with efficiency compression of microwave magnetic field is designed by a partially filled dielectric in this paper. Experimental results show that this method can achieve spin-wave linewidth measurement with lower RF power compare to the original rectangular cavity. Simultaneous, replacing the traditional tuned resonant cavity with the frequency adjustable signal source can reduce the system interference to cavity field distribution and lays the foundation for fully automated testing. Finally, the wide linewidth spin-wave linewidth test is realized in a low RF power environment, and the test uncertainty for the system is estimated within ±10 %.