Design and Optimization of a High-Efficiency 3D Multi-Tip Edge Coupler Based Lithium Niobate on Insulator Platform
Fiber-chip edge couplers can minimize mode mismatch in integrated lithium niobate (LiNbO<sub>3</sub>) photonics via facilitating broad optical bandwidth coupling between optical fibers and waveguide circuits. We designed a high-efficiency multi-tip edge coupler utilizing the lithium niob...
| Main Authors: | , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
MDPI AG
2024-01-01
|
| Series: | Photonics |
| Subjects: | |
| Online Access: | https://www.mdpi.com/2304-6732/11/2/134 |
| _version_ | 1797297218488631296 |
|---|---|
| author | Tian Zhang Jinye Li Mingxuan Li Jianguo Liu |
| author_facet | Tian Zhang Jinye Li Mingxuan Li Jianguo Liu |
| author_sort | Tian Zhang |
| collection | DOAJ |
| description | Fiber-chip edge couplers can minimize mode mismatch in integrated lithium niobate (LiNbO<sub>3</sub>) photonics via facilitating broad optical bandwidth coupling between optical fibers and waveguide circuits. We designed a high-efficiency multi-tip edge coupler utilizing the lithium niobate on insulator (LNOI) platform for achieving superior fiber-to-chip coupling. The device comprises a bilayer LN inversely tapered waveguide, three 3D inversely tapered waveguides, and a silicon oxynitride (SiON) cladding waveguide (CLDWG). Finite difference method (FDM) and eigenmode expansion (EME) simulations were utilized to simulate and optimize the edge coupler structure specifically within the 1550 nm band. This coupler demonstrates a low fiber-chip coupling loss of 0.0682/0.0958 dB/facet for TE/TM mode at 1550 nm when interfaced with a commercially cleaved single-mode fiber (SMF) with a mode field diameter (MFD) of approximately 8.2 μm. Moreover, the 1 dB bandwidth of the coupler is 270 nm for the TE mode and 288 nm for the TM mode. Notably, the coupler exhibits a relatively large tolerance for optical misalignment owing to its large mode spot size of up to 4 μm. Given its ultra-low loss, high-efficiency ultra-broadband capabilities, and substantial tolerance features, this proposed device provides a paradigm for fiber-to-chip edge coupling within lithium niobate photonics. |
| first_indexed | 2024-03-07T22:17:12Z |
| format | Article |
| id | doaj.art-9e0761f009b64c31a517292e6403e909 |
| institution | Directory Open Access Journal |
| issn | 2304-6732 |
| language | English |
| last_indexed | 2024-03-07T22:17:12Z |
| publishDate | 2024-01-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Photonics |
| spelling | doaj.art-9e0761f009b64c31a517292e6403e9092024-02-23T15:31:38ZengMDPI AGPhotonics2304-67322024-01-0111213410.3390/photonics11020134Design and Optimization of a High-Efficiency 3D Multi-Tip Edge Coupler Based Lithium Niobate on Insulator PlatformTian Zhang0Jinye Li1Mingxuan Li2Jianguo Liu3State Key Laboratory on Integrated Optoelectronics, Institute of Semiconductors, Chinese Academy of Sciences, Beijing 100083, ChinaState Key Laboratory on Integrated Optoelectronics, Institute of Semiconductors, Chinese Academy of Sciences, Beijing 100083, ChinaState Key Laboratory on Integrated Optoelectronics, Institute of Semiconductors, Chinese Academy of Sciences, Beijing 100083, ChinaState Key Laboratory on Integrated Optoelectronics, Institute of Semiconductors, Chinese Academy of Sciences, Beijing 100083, ChinaFiber-chip edge couplers can minimize mode mismatch in integrated lithium niobate (LiNbO<sub>3</sub>) photonics via facilitating broad optical bandwidth coupling between optical fibers and waveguide circuits. We designed a high-efficiency multi-tip edge coupler utilizing the lithium niobate on insulator (LNOI) platform for achieving superior fiber-to-chip coupling. The device comprises a bilayer LN inversely tapered waveguide, three 3D inversely tapered waveguides, and a silicon oxynitride (SiON) cladding waveguide (CLDWG). Finite difference method (FDM) and eigenmode expansion (EME) simulations were utilized to simulate and optimize the edge coupler structure specifically within the 1550 nm band. This coupler demonstrates a low fiber-chip coupling loss of 0.0682/0.0958 dB/facet for TE/TM mode at 1550 nm when interfaced with a commercially cleaved single-mode fiber (SMF) with a mode field diameter (MFD) of approximately 8.2 μm. Moreover, the 1 dB bandwidth of the coupler is 270 nm for the TE mode and 288 nm for the TM mode. Notably, the coupler exhibits a relatively large tolerance for optical misalignment owing to its large mode spot size of up to 4 μm. Given its ultra-low loss, high-efficiency ultra-broadband capabilities, and substantial tolerance features, this proposed device provides a paradigm for fiber-to-chip edge coupling within lithium niobate photonics.https://www.mdpi.com/2304-6732/11/2/134edge couplersfiber-to-chip couplingthin-film lithium niobate3D multi-tip |
| spellingShingle | Tian Zhang Jinye Li Mingxuan Li Jianguo Liu Design and Optimization of a High-Efficiency 3D Multi-Tip Edge Coupler Based Lithium Niobate on Insulator Platform Photonics edge couplers fiber-to-chip coupling thin-film lithium niobate 3D multi-tip |
| title | Design and Optimization of a High-Efficiency 3D Multi-Tip Edge Coupler Based Lithium Niobate on Insulator Platform |
| title_full | Design and Optimization of a High-Efficiency 3D Multi-Tip Edge Coupler Based Lithium Niobate on Insulator Platform |
| title_fullStr | Design and Optimization of a High-Efficiency 3D Multi-Tip Edge Coupler Based Lithium Niobate on Insulator Platform |
| title_full_unstemmed | Design and Optimization of a High-Efficiency 3D Multi-Tip Edge Coupler Based Lithium Niobate on Insulator Platform |
| title_short | Design and Optimization of a High-Efficiency 3D Multi-Tip Edge Coupler Based Lithium Niobate on Insulator Platform |
| title_sort | design and optimization of a high efficiency 3d multi tip edge coupler based lithium niobate on insulator platform |
| topic | edge couplers fiber-to-chip coupling thin-film lithium niobate 3D multi-tip |
| url | https://www.mdpi.com/2304-6732/11/2/134 |
| work_keys_str_mv | AT tianzhang designandoptimizationofahighefficiency3dmultitipedgecouplerbasedlithiumniobateoninsulatorplatform AT jinyeli designandoptimizationofahighefficiency3dmultitipedgecouplerbasedlithiumniobateoninsulatorplatform AT mingxuanli designandoptimizationofahighefficiency3dmultitipedgecouplerbasedlithiumniobateoninsulatorplatform AT jianguoliu designandoptimizationofahighefficiency3dmultitipedgecouplerbasedlithiumniobateoninsulatorplatform |