UCLA

Antennas are fundamental elements of nearly all modern communication systems. As electronic devices become smaller, the antennas that operate within them must reduce in size as well. Traditional antennas radiate electromagnetic waves using a conducting electric current. As a result, their dimensions must ideally be on par with electromagnetic wavelength they transmit and receive, making it difficult to appreciably miniaturize antennas for mobile applications. Multiferroic antennas are offered as a possible solution to this problem. Coupling the physical properties of magnetostrictive and piezoelectric materials results in the conversion between magnetic flux and voltage. Because these antennas use an acoustic wave to generate radiation instead of a conduction current, their resonant wavelength sees a reduction in characteristic length by 5 orders-of-magnitude for a given frequency. In this experiment, multiferroic cantilevers are tested in order to study their nonlinear behavior when wirelessly actuated and how it is affected by tuning a bias magnetic field. The multiferroic cantilever is measured in a vacuum chamber, and wirelessly actuated by coils driven by a function generator. Magnetic field strength is measured with a Hall effect sensor. Cantilever displacement and voltage generated for several drive powers is measured as a function of frequency by a laser Doppler vibrometer and spectrum analyzer. This data is then used to characterize the strength of linear and nonlinear wireless actuation of multiferroic cantilevers.