Recent advancements in optical metrology, highlighted in a study led by Prof. Lixin Guo from Xidian University, reveal the transformative role of orbital angular momentum (OAM). Traditional optical metrology, based on interference principles, is evolving as researchers incorporate OAM, enabling enhanced motion tracking, including rotational dynamics. By utilizing OAM light, scientists can achieve innovative measurement techniques, such as 3D particle tracking, leveraging a modern interpretation of the Doppler effect that accounts for frequency shifts influenced by OAM and polarization.
Prof. Andrew Forbes notes that this integration allows for tracking motion in any direction, revolutionizing metrology for dynamic systems. The researchers propose the OAM spectrum as a ‘signature’ that changes when OAM light passes through complex media, providing valuable data. The analysis of this OAM fingerprint through machine learning and AI facilitates real-time recognition of complex environments, marking a significant advancement in the field. The review also explores quantum metrology using OAM, although this area is still emerging with significant potential. Overall, the study presents a comprehensive overview of applications ranging from nanoscale sensing to astrophysical measurements, contributing to advancements in both classical and quantum metrology.
