[en] Ultrasound is a powerful tool for diagnosing medical and mechanical problems. Conventional ultrasonics work at megahertz frequencies and with wavelengths of 1-2mms to 10’s mm. This means it cannot "see" very small objects at the nanoscale. Our new transducers are so small it is impractical to communicate with them electrically. Instead we have devised a non contact method of talking to them using short pulses of laser light.
We have adopted two approaches for producing these transducers, one method builds plates devices the other uses self assembled nanoparticles. The transducers are made from alternating metal and soft transparent layers. They have optical and mechanical resonances and so the devices have to be made such that they work well both mechanically and optically