(color online) (a) Dispersion of the structure with the width of the line defect m, in which the isolated mode with a flat pass band is marked by circles. The profile of the localized modes with the frequency of 103.5 MHz for acoustic field (b) and electromagnetic field (c) in one supercell. (d) Acoustic field (the strain is magnified for clarity) and (e) electromagnetic field at the frequency of 103.5 MHz transmitting along the line defect obtained by the frequency-domain simulations.