Plasmon-induced photoacoustic transducer for non-invasive skin tightening

This paper reports a plasmon-induced photoacoustic transducer for non-invasive skin tightening using a laser diode and an ultrathin nanoplasmonic optical absorber. The nanoplasmonic absorber consists of three-dimensional Au nanoislands (Au NIs) with high optical absorption and polydimethylsiloxane (PDMS) thin film with high thermal expansion coefficient. The low-cost and compact laser diode (LD) significantly scales down the conventional photoacoustic system based on bulk solid-state lasers and excites the nanoplasmonic absorber with sufficient optical energy to generate MHz-scale ultrasound. This plasmon-induced photoacoustic transducer opens new opportunities for ultrasound in dermatology, extending its application to portable at-home skin-care device.