“新质装备前沿讲堂”第四十一场：苏众庆教授——基于飞秒激光超声技术的芯片内部表征及声流控

苏众庆，现为香港理工大学智慧结构与系统讲席教授、机械工程学系系主任、及教育部“长江学者”****，并自2019年起出任Elsevier旗下Ultrasonics期刊主编，同时兼任香港力学学会副会长。于北京航空航天大学航空工程与科学学院获得航空学学士学位，继而在悉尼大学航空、机械与机电工程学院获得博士学位。研究方向主要涵盖超声波学、波传导、结构健康监测、传感器、无损检测、智能材料与复合材料。除出任Ultrasonics期刊主编外，目前或曾经担任9个该领域主要期刊的副主编，包括Journal of Sound and Vibration、 Structural Health Monitoring: An International Journal等。担任多个国际会议的主席，包括2018年在香港举办的第七届亚太国际健康监测技术大会、2023年在美国举办的SPIE Conference on Sensors & Smart Structures Technologies for Civil, Mechanical & Aerospace Systems、及2024年在美国举行的SPIE Conference on Health Monitoring of Structural and Biological Systems。2022年当选International Institute of Acoustics and Vibration 杰出会士(Distinguished Fellow)。

Path-breaking advances in ultrafast laser technology have shed new light on optical–acoustic coupling and opened up intriguing application prospects. In this talk, we will report on a new nondestructive evaluation framework based on ultrafast laser ultrasonics, from fundamental theory to implementation details. Making use of the ultrashort acoustic wavelength of laser-generated ultrasound, the femtosecond-laser-enabled ultrasonics techniques have enabled super high-resolution material characterization at the nanoscale. The approach has been experimentally demonstrated by characterizing the monocrystalline semiconductor wafers which are of a high degree of anisotropy, and imaging interior features of an opaque, stacked micro-system, three-dimensionally and contactlessly. In addition, we also present some new application paradigms of the ultrafast laser in picosecond acoustofluidics research. We develop a photoacoustic tweezer, integrating the merits from optical and acoustic tweezers. Via a transient thermoelastic coupling, the pulsed ultrafast laser irradiates a substrate through liquid, to create ring-shaped travelling photoacoustic tweezers and generate acoustic radiation forces for manipulating tiny particles in the liquid, also in a noncontact manner.