The Theoretical Study Of The Coupling Interactions Between YIG/Terfenol-D/PZT Trilayer Films

In order to make more effective use of frequency spectrum and improve the data transmission rate, tunable filters have been widely and continuously playing an important role to meet demands in both modern various commercial signal processing systems and military radar systems. Based on GGG/YIG/epoxy/electrode/PZT/electrode multilayer film structure, magnetostrictive phase rare-earth-iron alloy(Terfenol-D), which can not only exhibit giant magnetostrictive effect but be used as electrode of PZT, was introduced to substitute the epoxy/electrode, and a higher conversion efficiency multiferroic GGG/YIG/Terfenol-D/PZT/electrode trilayer films structure was proposed. In this structure, the core component YIG/Terfenol-D/PZT can make electric field to control the working frequency of filter. The interactions between YIG/Terfenol-D/PZT trilayer films have been exactly investigated by theory and simulation in this paper, and the main contents are as follows.1. An equivalent circuit approach was used to analyze the DME and IME of Terfenol-D/PZT bilayer films. The results revealed that the magnetoelectric voltage coefficient and inverse magnetoelectric coefficient reached the maximum when the volume fraction of PZT is about 0.4, and increased with the increase of d31 P of PZT layer and d33 m of Terfenol-D layer. When Terfenol-D was saturation magnetized, we found that the saturation magnetization orientation of Terfenol-D layer can be tuned by electric field E on PZT.2. The physical model of YIG/Terfenol-D bilayer films was presented, and the magnetic exchange-coupled interaction of Terfenol-D/YIG bilayer was investigated by the principle of minimum energy. The magnetic exchange-coupled relationship between saturation magnetization M1 of YIG and saturation magnetization M2 of Terfenol-D was obtained. The results revealed that when the magnetic field ranges from 0 Oe to 3000 Oe in the scope of actual application, the direction of saturation magnetization M1 of YIG will keep parallel with the direction of saturation magnetization M2 of Terfenol-D, so that the external magnetic field can adjust the direction of saturation magnetization M1 of YIG by adjusting the direction of saturation magnetization M2 of Terfenol-D.3. The coupling interactions between YIG/Terfenol-D/PZT trilayer were investigated based on magnetoelectric interactions of Terfenol-D/PZT bilayer and magnetic exchange-coupled interaction of Terfenol-D/YIG bilayer. The results of calculation and simulation demonstrated that the external magnetic field can tune the direction of saturation magnetization M1 of YIG in a large range, while the electric field on PZT can tune the direction of saturation magnetization M1 of YIG in a relatively small range.4. MATLAB was used to simulate the magnetoelectric effect of Terfenol-D/PZT bilayer films, the magnetic exchange coupling interaction of YIG/Terfenol-D bilayer films and coupling interactions between YIG/Terfenol-D/PZT trilayer films. The comparison of our numerical simulations and previous researches confirmed the correctness of our calculations and simulations. Some optimal experimental parameters were obtained to guide the future experimental work and further research.