Effect of stress on guided EM waves in anisotropic dielectric plates

The changes in the frequencies or velocities of guided EM (electromagnetic) waves in infinite and anisotropic dielectric plates affected by uniform and thickness-dependent stress fields are studied. For the uniformly applied stresses, frequency changes as a function of wavenumber are computed based on exact solutions of the 3-D Maxwell equations. For the thickness-dependent stress fields, such as those caused by the steady accelerations in plates attached to a rigid base, frequency changes are computed based on the variational techniques and the Rayleigh-Ritz method. For numerical computations, a dielectric plate of lithium niobate with thickness 2b = 3.27 mm is considered. It is found that the maximum frequency shift is about (1 /spl sim/ 2) /spl times/ 10/sup -5/ for the uniformly applied stress of 1MPa. For steady acceleration on plates attached to a rigid base, the maximum frequency shift is about (3 /spl sim/ 15) /spl times/ 10/sup -10//g for 2b = 3.27 mm.<<ETX>>