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 Karl Franzens University Graz

Graz University of Technology 

Sensing with Structured Beams
Martin Lavery
University of Glasgow
16:15 - 17:15 Tuesday 19 January 2021 Live Online Presentation and Discussion via Zoom

Structured beams are optical fields that are generated to have very specific spatially patterned phase and intensity profiles. There are a wide variety of these beams that interact with media and the environments in unique ways depending on their spatial profile. In this talk we will discuss the use of these beams for the amplification of very small non-linear acoustic behaviour in air, the determination of particulate size based on optical aberrations, and, when coupled with machine learning, for revealing usually unobservable physical parameters in the environment.

Fig. 1: Example of structured beams with twisted wavefronts, known as orbital angular momentum beams, (a). Locally the direction of propagation is skewed, (b), which can lead to unique and interesting interactions with materials and the environments. For acoustic systems, this skewing can lead to variation in non-linear chirping across the wavefront that when interfering during propagation can lead to an amplification of usually unnoticeable non-linear behaviour, (c).