Generation and applications of broadband high-frequency laser ultrasound with nanostructured materials
25 January 2022 • 2:15 PM - 2:30 PM PST | Room 211 (Level 2 South)
In the present work we show that the interaction between short lasers pulses and tailor-made nanostrucured materials can produce broadband high-frequency ultrasound. In order to obtain efficient light-to-pressure conversion we used nanostructured carbon nanotubes permeated with high thermal expansion polydimethylsiloxane and nanometric TiO2 particles with adsorbed dye infused polystyrene. It is possible to achieve ultrasound pulses with central frequencies of 80 MHz and bandwidths of 125 MHz (at -6 dB) using a 6 ns pulsed laser. The aforementioned materials are used in order to establish proof-of-concept of the non-destructive ultrasound pulses interaction with biological membranes, exemplified by the unloading of Green Fluorescence Protein from giant unilamellar vesicles, and of non-invasive material inspection, illustrated with the measurement of the thickness of thin paint layers based on ultrasound frequency attenuation.
Univ. de Coimbra (Portugal), LaserLeap Technologies (Portugal)
Carlos Serpa (BSc Chemistry, 1995; MSc Physical Chemistry, 2000; PhD Photochemistry, 2004) is Assistant Professor at the University of Coimbra (Portugal). In 2005 took a research position in Bioinorganic Chemistry at Caltech. He was then one among the first researchers to earn a national portuguese R&D system position (Starting and Developing Grants). His scientific interests are in the field of interactions between Light and Materials, focused in Piezophotonic Materials and nanostructured Materials for renewable Energy and Health applications. Co-author of over fifty papers in international peer reviewed journals, over 150 conference proceedings, three book chapters, and one family of patents, granted in 35 countries, licensed to a start-up company emerged from his research. Managing Director of the Coimbra Laser Lab. Managed several projects and distinguished with several prizes related with his research and with the introduction in the market of the first piezophotonic materials.