Pixelated metasurfaces for linear-polarization conversion and absorption

Abstract

Terahertz metasurfaces with pixelated meta-atoms were designed for linear-polarization conversion and absorption. The differences between the two functionalities emerged from the number and arrangement of metal-dielectric combos patching some but not necessarily every pixel of each meta-atom. A patching arrangement for a meta-atom with $3\times 3$ pixels yielded polarization conversion ratio (PCR) $>0.9$ over the 10.20–16.08 THz band, whereas another yielded absorptance (A) $>0.9$ over the 27.67–28.73 THz band. A third patching arrangement delivered both functionalities, albeit in different spectral regimes: high PCR and high A at 13.92 THz and 29.1 THz, respectively. The spatial profiles of the electric and magnetic fields in each meta-atom suffice to explain the display of these functionalities. The generality of the pixelated meta-atom approach was supported by a meta-atom with $4\times 4$ pixels.

Keywords:

• Metasurface
• pixelated meta-atom
• absorber
• polarization converter

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

This work was supported by Science and Engineering Research Board [grant number ECR/2017/001485].

Notes on contributors

Rajan Agrahari

Rajan Agrahari is an assistant professor at the National Institute of Technology Patna, Bihar, India. He received Ph.D. degree from the Indian Institute of Technology (BHU), Varanasi, India in 2019. His current areas of research include nanophotonics, plasmonics, and metamaterials.

Akhlesh Lakhtakia

Akhlesh Lakhtakia is the Evan Pugh University professor and Charles Godfrey Binder professor of Engineering Science and Mechanics at The Pennsylvania State University. He is currently interested in surface waves, solar cells, sculptured thin films, biologically inspired design, mimumes, bioreplication, and forensic science. He has been elected a fellow of OSA, SPIE, AAAS, APS, IEEE, IoP, RSC, and RSA. He received the 2010 SPIE Technical Achievement Award, the 2016 Walston Chubb Award for Innovation, and the 2022 SPIE Smart Structures and Materials Lifetime Achievement Award.

Pradip Kumar Jain

Pradip Kumar Jain received B.Tech., M.Tech., and Ph.D. degrees from the Indian Institute of Technology (BHU), Varanasi, India, in 1979, 1981, and 1988, respectively. He became a full professor of electronics engineering at the same institution in 2001. He is currently the Director of the National Institute of Technology Patna, Bihar, India. A fellow of the Institution of Electronics and Telecommunication Engineers, India, he is interested in microwave/millimeter-wave devices and circuits, and high-power microwave electron-beam devices.

Somak Bhattacharyya

Somak Bhattacharyya received B.Sc., B.Tech., and M.Tech. degrees from the University of Calcutta, India and Ph.D. from the Indian Institute of Technology Kanpur, India. He is currently serving as assistant professor in the Indian Institute of Technology (BHU), Varanasi, India. He has received the URSI Young Scientist Award thrice. He is Associate Fellow of West Bengal Academy of Science & Technology, Fellow of Optical Society of India and Institution of Electronics and Telecommunication Engineers, India, as well as Senior Member of IEEE. His current areas of interest include metasurfaces, periodic structures, opto-microwave devices, and microwave photonics.