Caltech Engineers Develop One-way Transmission System for Sound Waves

Caltech researchers have created the first tunable acoustic diode-a device that allows acoustic information to travel only in one direction, at controllable frequencies. "...we may be able to scavenge sound energy from undesired structural vibrations in machinery by controlling the flow of sound waves away from the machinery and into a transducer. The transducer would then convert the sound waves into electricity." [MORE]