Sv. Biryukov et Vg. Polevoi, THE ELECTROSTATIC PROBLEM FOR THE SAW INTERDIGITAL TRANSDUCERS IN AN EXTERNAL ELECTRIC-FIELD .2. PERIODIC STRUCTURES, IEEE transactions on ultrasonics, ferroelectrics, and frequency control, 43(6), 1996, pp. 1160-1170
An exact solution of the electrostatic problem for calculating the sur
face charge and electric field distributions in an arbitrary periodic
interdigital transducer (IDT) is given using the results of our compan
ion paper [1], An arbitrary external electric field may be specified a
long the electrode structure with the unit cell containing one electro
de, or several electrodes, of different widths, The potentials of the
electrodes that may be specified are also arbitrary, It is shown that
in the case without an external field, the solution includes all the k
nown results as special cases, The case of shorted electrodes in the e
xternal electric field is investigated in detail, The surface charge a
nd electric field distributions are calculated for a spatially harmoni
c external field with an arbitrary wavenumber, The results of the calc
ulations are represented graphically for various ratios between the pe
riod of the electrode structure and the wavelength of the external fie
ld for the case of a unit cell containing one or two electrodes of dif
ferent widths.