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Ultralow-loss optical interconnect enabled by topological unidirectional guided resonance
Haoran Wang1, Yi Zuo1, Xuefan Yin1,2
1State Key Laboratory of Advanced Optical Communication Systems and Networks, Department of Electronics & Frontiers Science Center for Nano-optoelectronics, Peking University, Beijing 100871, China.
Science Advances
|March 20, 2024
Summary
We developed ultralow-loss grating couplers using unidirectional guided resonances (UGRs). This breakthrough significantly improves energy efficiency for optical interconnects, enabling large-scale photonic integration.
Area of Science:
- Photonics
- Optoelectronics
- Materials Science
Background:
- Grating couplers are essential for connecting photonic chips to external devices.
- Current grating couplers suffer from low energy efficiency, limiting large-scale photonic integration.
Purpose of the Study:
- To develop ultralow-loss grating couplers.
- To enhance energy efficiency in optical interconnects.
- To overcome limitations in current photonic integration technologies.
Main Methods:
- Utilizing unidirectional guided resonances (UGRs) to suppress downward radiation.
- Engineering grating dispersion.
- Apodizing grating geometry.
- Experimental realization and characterization of the grating coupler.
Main Results:
- Achieved a record-low grating coupler loss of -0.34 dB.
- Demonstrated a 1-dB bandwidth exceeding 30 nm at 1550 nm.
- Realized an optic via with a loss of only -0.94 dB.
Conclusions:
- Unidirectional guided resonances offer a systematic approach to achieving energy-efficient optical interconnects.
- The developed grating couplers pave the way for large-scale photonic integration.
- This method is applicable to various grating geometries.
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