On electrostatics of finite planar system of strips applied in surface acoustic wave interdigital transducers

• Autorzy: Tasinkevych V. , Danicki E. J.
• Języki publikacji: EN

Abstrakty

EN

Planar systems of strips placed on a piezoelectric body are exploited in interdigital transducers for generation, detection and reflection of surface waves. The spatial field distribution in the plane of strips exhibits square-root singularities at the strips edges. In effect, the evaluation of charge spatial spectrum by direct application of the Fourier transformation to the spatial charge distribution never yields satisfactory accuracy. This is due to the strong dependence of the spectrum on the distribution details over the entire system. A new method is proposed here for direct evaluation of the spatial spectrum; the spatial distribution is obtained from it by the inverse Fourier transformation for certain auxiliary purposes and final verification of numerical results. The solution is constructed as a linear combination of the template functions, evaluated in spectral domain and satisfying the electric boundary conditions on the strips. The same functions are applied in the solution of the complementary problem of strips embedded in a preexisting electric field, assumed to be spatially variable (harmonic). In this case the strip total charge is evaluated dependent on the preexisting ("incident") field, as well as the Bloch harmonics of the "scattered" field in a wide spectral domain. Particular attention is dedicated to the numerical problems arising in evaluation of the template functions and the final charge spectrum. The computed examples show typical computational errors and how they were corrected by improving the numerical procedures.

Słowa kluczowe

EN

surface acoustic wave

PL

przetwornik akustyczny; fala akustyczna powierzchniowa; piezoelektryk; rozkład ładunku w przetworniku akustycznym; pole elektryczne w przetworniku akustycznym

• Wydawca: Instytut Podstawowych Problemów Techniki PAN
• Czasopismo: Journal of Technical Physics
• Rocznik: 2005
• Tom: Vol. 46, no 3
• Strony: 175--193
• Opis fizyczny: Bibliogr. 19 poz., wykr.

Twórcy

autor

Tasinkevych V.

• Institute of Fundamental Technological Research, Polish Academy of Sciences, Świętokrzyska 21, 00-049 Warszawa

autor

Danicki E. J.

• Institute of Fundamental Technological Research, Polish Academy of Sciences, Świętokrzyska 21, 00-049 Warszawa

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