Electronically variable delay using ferroelastic-ferroelectrics

Coupled ferroelastic-ferroelectric domains in the rare-earth molybdates can be used to provide electronically variable analog delay in simple acoustic delay line structures. Delay variations of ∼3% for surface acoustic waves and 12% for bulk longitudinal waves are demonstrated with gadolinium molybdate [Gd2 (MoO4)3] crystals. Estimates of a number of parameters useful in evaluating device performance are made from experimental measurements.