Metasurface optics with on-axis polarization control for terahertz sensing applications

Nowack, T. S. , Shah, Y. D. , Grant, J. P. , Escorcia Carranza, I. , Kenney, M. G. , Faccio, D. , Wasige, E. and Cumming, D. R.S. (2023) Metasurface optics with on-axis polarization control for terahertz sensing applications. IEEE Transactions on Terahertz Science and Technology, 13(4), pp. 373-380. (doi: 10.1109/TTHZ.2023.3263648)

Abstract

Non-destructive testing and imaging of materials with unknown properties are important applications of terahertz technology. Different contrast forming methods are available to obtain diverse information on the imaged region, including intensity, color, phase and polarization. Polarimetric imaging is relatively under-investigated owing to the difficulty in its implementation with complex optical arrangements. In this paper we present the design and monolithic fabrication of an anisotropic metasurface that incorporates several beam forming functions in a single layer with high efficiency thus simplifying instrument construction. The probe beam generated by the metasurface consists of an orthogonally polarized pair of collinear Bessel beams that create a well-defined on-axis change of polarization. The metasurface is integrated into a polarimetric imaging microscope for 3D beam profiling and sensing experiments at 2.52 THz. An analytical model to describe the on-axis polarization variation was found to be in excellent agreement with both finite-difference time-domain (FDTD) simulations and the experimental results. The setup was used to measure the refractive index and diattenuation of homogeneous sample regions in a proof-of-principle application. We anticipate this technology will find future application in non-destructive testing and polarimetric imaging of polymer composites and 3D profilometry of reflective surfaces.

• Item Type: Articles
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Wasige, Professor Edward and Nowack, Mr Thomas and Kenney, Dr Mitchell Guy and Escorcia Carranza, Dr Ivonne and Grant, Dr James and Cumming, Professor David and Faccio, Professor Daniele and Shah, Dr Yash Diptesh
• Authors: Nowack, T. S., Shah, Y. D., Grant, J. P., Escorcia Carranza, I., Kenney, M. G., Faccio, D., Wasige, E., and Cumming, D. R.S.
• College/School: College of Science and Engineering > School of Engineering; College of Science and Engineering > School of Engineering > Electronics and Nanoscale Engineering; College of Science and Engineering > School of Engineering > James Watt Nanofabrication Centre; College of Science and Engineering > School of Physics and Astronomy
• Journal Name: IEEE Transactions on Terahertz Science and Technology
• Publisher: IEEE
• ISSN: 2156-342X
• ISSN (Online): 2156-3446
• Published Online: 31 March 2023
• Copyright Holders: Copyright © 2023 IEEE
• First Published: First published in IEEE Transactions on Terahertz Science and Technology 13(4):373 - 380
• Publisher Policy: Reproduced in accordance with the publisher copyright policy
• Data DOI: 10.5525/gla.researchdata.1407

Project Code	Award No	Project Name	Principal Investigator	Funder's Name	Funder Ref	Lead Dept
302077		Doctoral Training Network in Terahertz Technologies for Imaging, Radar and Communication Applications	Edward Wasige	European Commission (EC)	N/A	ENG - Electronics & Nanoscale Engineering
305567		QuantIC - The UK Quantum Technoogy Hub in Quantum Enhanced Imaging	Miles Padgett	Engineering and Physical Sciences Research Council (EPSRC)	EP/T00097X/1	P&S - Physics & Astronomy