Steering abrupt autofocusing beams with metasurfaces [Invited]

Research output: Journal Publications and ReviewsRGC 21 - Publication in refereed journalpeer-review

2 Scopus Citations
View graph of relations

Detail(s)

Original languageEnglish
Pages (from-to)D1-D7
Journal / PublicationJournal of the Optical Society of America B: Optical Physics
Volume41
Issue number11
Online published28 Jun 2024
Publication statusPublished - Nov 2024

Abstract

Abrupt autofocusing (AAF) beams, known for their non-diffractive properties, extended focal depth, and self-healing capabilities, are advantageous over conventional Gaussian beams in the biomedical field. Compared to the previous method that can only generate a passive AAF beam, we introduce metasurfaces to achieve a dynamically steered AAF beam at the incident wavelength of 532 nm. By rotating the two metasurfaces in opposite directions of an angle 𝜃, both the generated position of the AAF beam and the autofocusing direction can be altered. Our theoretical analysis and full-wave simulation results confirmed that the deflection angle of the AAF beam can be finely adjusted from −11° to 11° without significantly affecting the focal length or focusing efficiency. This capability allows for precision operation in biomedical applications, including enhanced laser surgery, optical tweezing, and optimized photodynamic therapy. © 2024 Optica Publishing Group.