Low-loss grating coupler with a subwavelength structure on a thin-film lithium niobate substrate.
Opt Lett
; 49(2): 222-225, 2024 Jan 15.
Article
em En
| MEDLINE
| ID: mdl-38194533
ABSTRACT
We demonstrated a low-loss O-band grating coupler on an x-cut thin-film lithium niobate substrate by implementing subwavelength and apodized structures. The subwavelength gratings were used to mitigate the refractive index discontinuity between the input taper and grating region, which was the first application of such a structure for grating coupler optimization on a thin-film lithium niobate substrate. The coupling efficiency was measured to be -1.99â
dB/coupler at a wavelength of 1312.8â
nm, which was the lowest loss among the reported lithium niobate grating couplers that do not use metal mirrors. The proposed design does not require metal mirrors or any additional material layers and can be easily fabricated with a single-step lithography and etching processes.
Texto completo:
1
Base de dados:
MEDLINE
Idioma:
En
Revista:
Opt Lett
Ano de publicação:
2024
Tipo de documento:
Article