Revealing Structural Disorder in Hydrogenated Amorphous Silicon for a Low-Loss Photonic Platform at Visible Frequencies
© 2021 Wiley-VCH GmbH.
| Publié dans: | Advanced materials (Deerfield Beach, Fla.). - 1998. - 33(2021), 9 vom: 12. März, Seite e2005893 |
|---|---|
| Auteur principal: | |
| Autres auteurs: | , , , , , |
| Format: | Article en ligne |
| Langue: | English |
| Publié: |
2021
|
| Accès à la collection: | Advanced materials (Deerfield Beach, Fla.) |
| Sujets: | Journal Article dielectric metasurfaces hydrogenated amorphous silicon low-loss materials nano-crystalline plasma-enhanced chemical vapor deposition |
| Résumé: | © 2021 Wiley-VCH GmbH. The high refractive index of hydrogenated amorphous silicon (a-Si:H) at optical frequencies is an essential property for the efficient modulation of the phase and amplitude of light. However, substantial optical loss represented by its high extinction coefficient prevents it from being utilized widely. Here, the bonding configurations of a-Si:H are investigated, in order to manipulate the extinction coefficient and produce a material that is competitive with conventional transparent materials, such as titanium dioxide and gallium nitride. This is achieved by controlling the hydrogenation and silicon disorder by adjusting the chemical deposition conditions. The extinction coefficient of the low-loss a-Si:H reaches a minimum of 0.082 at the wavelength of 450 nm, which is lower than that of crystalline silicon (0.13). Beam-steering metasurfaces are demonstrated to validate the low-loss optical properties, reaching measured efficiencies of 42%, 62%, and 75% at the wavelengths of 450, 532, and 635 nm, respectively. Considering its compatibility with mature complementary metal-oxide-semiconductor processes, the low-loss a-Si:H will provide a platform for efficient photonic operating in the full visible regime |
|---|---|
| Description: | Date Revised 02.03.2021 published: Print-Electronic Citation Status PubMed-not-MEDLINE |
| ISSN: | 1521-4095 |
| DOI: | 10.1002/adma.202005893 |