Demonstration of a bi-directionally tunable arrayed waveguide grating with ultra-low thermal power using S-shaped...

Area of Science:

• Photonics and Optical Engineering
• Integrated Optics
• Semiconductor Devices

Background:

• Arrayed waveguide gratings (AWGs) are crucial for wavelength division multiplexing (WDM).
• Tuning AWG spectral responses is essential for system stability and flexibility.
• Silicon-on-insulator (SOI) platforms offer high index contrast, enabling compact device designs.

Purpose of the Study:

• To propose and demonstrate a thermally bi-directionally tunable arrayed waveguide grating (TBDTAWG) on an SOI platform.
• To achieve both red- and blue-shift tuning using complementary phase distributions in an S-shaped architecture.
• To validate the device's performance through measurements and simulations for WDM applications.

Main Methods:

• Fabrication of a TBDTAWG device utilizing passive and active designs on an SOI platform.
• Implementation of an S-shaped architecture to accommodate short waveguide length differences.
• Utilizing two triangular thermal-tuning regions with complementary phase distributions for bi-directional tuning.
• Characterization of spectral responses and tuning performance using electrical voltage and optical power.

Main Results:

• Demonstration of both red- and blue-shifted spectral tuning.
• Achieved a linear bi-directional shift-to-power ratio of ±30.5 nm/W.
• Obtained a wide tuning range of 8 nm within an electrical voltage range of 0-2.5 V.
• Measurement results showed good agreement with 2D simulation results.

Conclusions:

• The proposed TBDTAWG on SOI platform successfully achieves bi-directional spectral tuning.
• The device exhibits excellent tuning linearity and a wide tuning range.
• The TBDTAWG shows significant potential for spectral stabilization in WDM communication systems via feedback control.