RIKEN Achieves Ultra-Low Loss Optical Waveguides with Silicon Nitride (SiN) Photonics, Advancing Next-Gen Optical Technology

理化学研究所 (RIKEN) プレスリリース Japan

Overview

RIKEN has announced successful development of optical waveguides using Silicon Nitride (SiN) photonics technology, achieving significantly lower optical loss compared to existing silicon photonics. This ultra-low loss waveguide minimizes signal attenuation over long distances and enables the construction of complex optical circuits. Applications are anticipated in quantum photonics, optical frequency combs, and high-precision sensing like LiDAR. SiN’s broad wavelength compatibility from visible to near-infrared positions it for diverse optical device applications.

In Depth

The Potential of Silicon Nitride (SiN) Photonics

Silicon photonics has become a crucial platform for optical device integration due to its high compatibility with semiconductor manufacturing processes. However, conventional silicon-on-insulator (SOI) based waveguides sometimes face challenges with optical loss, particularly in long-distance transmission and complex optical circuits. To address this, Silicon Nitride (SiN) photonics is emerging as a next-generation high-performance photonic platform.

RIKEN’s Achievement in Ultra-Low Loss Optical Waveguides

RIKEN (Rikagaku Kenkyusho) has announced the successful development of optical waveguides utilizing SiN photonics technology, achieving significantly lower optical loss compared to previous silicon-based waveguides. This technological breakthrough is profoundly important for several reasons:

• Ultra-Low Propagation Loss: Achieves extremely low propagation loss, below 0.1 dB/cm, minimizing optical signal attenuation and enabling longer-distance data transmission and the construction of more complex optical circuits.
• Broad Transparency Window: Compatible with a wide range of wavelengths from visible to near-infrared, allowing for diverse optical devices and applications.
• Excellent Nonlinear Optical Properties: Contributes to advanced signal processing functions and the realization of new wavelength division multiplexing schemes.
• Superior Thermal Stability: Compared to silicon, SiN has a lower thermo-optic coefficient, resulting in less wavelength drift due to temperature changes, ensuring stable operation even in environments with large temperature fluctuations, such as data centers.

Diverse Applications and Industrialization Prospects

This ultra-low loss SiN optical waveguide technology is expected to find applications in various cutting-edge fields:

• Quantum Photonics: When integrated with liquid crystals, it enables low-power, reconfigurable quantum interferometers, forming a foundation for scalable quantum photonic circuits.
• High-Precision Sensing: Facilitates high-precision measurements and wide field-of-view, low-noise operation in optical frequency combs and LiDAR systems.
• Long-Haul Optical Communication: Overcomes the limitations of traditional SOI platforms, supporting hundreds of channels in DWDM systems and enabling more complex modulation formats.
• AI Data Centers: With high thermal stability, and through the combination of AI-driven process optimization and robotics, automated fabrication of complex SiN photonic chips (achieving over 95% first-pass yield) becomes possible, contributing to the stable supply of high-speed data transmission infrastructure.

Given its exceptional properties and CMOS process compatibility, SiN photonics is anticipated to significantly contribute not only to further increasing capacity and reach in optical communication but also to the advancement of next-generation optical computing and sensor technologies. While challenges remain in further optimizing manufacturing processes and reducing costs for mass production, RIKEN’s achievement is set to greatly accelerate the industrialization of this field.