Wideband Chirped Acoustic Devices

We present a novel design for configurable wide-passband chirped acoustic devices. Chirped distributed acoustic reflection transducers (DARTs) are fabricated in wide-aperture linear and skewed delay-line conformations on 42° Y-LT/SiO2/Si substrates, allowing for the propagation of the fundamental and higher-order shear-horizontal surface acoustic wave modes. The transverse higher-order harmonics were strongly excited to achieve multi-resonance squeezing. Measured performance of fabricated devices demonstrates passbands of up to 17.1% fractional bandwidth. Two chirp configurations are demonstrated, one with a constant 250 ns group delay and another with a linearly varying delay from 100–550 ns across the passband.