Performance optimization of a metasurface incorporating non-volatile phase change material
Issued Date
2022-04-11
Resource Type
eISSN
10944087
Scopus ID
2-s2.0-85128153741
Pubmed ID
35472922
Journal Title
Optics Express
Volume
30
Issue
8
Start Page
12982
End Page
12994
Rights Holder(s)
SCOPUS
Bibliographic Citation
Optics Express Vol.30 No.8 (2022) , 12982-12994
Suggested Citation
Sakda N., Ghosh S., Chitaree R., Rahman B.M.A. Performance optimization of a metasurface incorporating non-volatile phase change material. Optics Express Vol.30 No.8 (2022) , 12982-12994. 12994. doi:10.1364/OE.453612 Retrieved from: https://repository.li.mahidol.ac.th/handle/20.500.14594/86923
Title
Performance optimization of a metasurface incorporating non-volatile phase change material
Author(s)
Author's Affiliation
Other Contributor(s)
Abstract
Optical metasurface is a combination of manufactured periodic patterns of many artificial nanostructured unit cells, which can provide unique and attractive optical and electrical properties. Additionally, the function of the metasurface can be altered by adjusting the metasurface's size and configuration to satisfy a particular required property. However, once it is fabricated, such specific property is fixed and cannot be changed. Here, phase change material (PCM) can play an important role due to its two distinct states during the phase transition, referred to as amorphous and crystalline states, which exhibit significantly different refractive indices, particularly in the infrared wavelength. Therefore, a combination of metasurface with a phase change material may be attractive for achieving agile and tunable functions. In this paper, we numerically investigate an array of silicon cylinders with a thin PCM layer at their centers. The GST and GSST are the most well-known PCMs and were chosen for this study due to their non-volatile properties. This structure produces two resonant modes, magnetic dipole and electric dipole, at two different resonating wavelengths. We have numerically simulated the effect of cylinder's height and diameter on the reflecting profile, including the effect of thickness of the phase change material. Additionally, it is shown here that a superior performance can be achieved towards reduced insertion loss, enhanced extinction ratio, and increased figure of merit when a GST layer is replaced by a GSST layer.