Integrated athermal arrayed-waveguide grating multiplexer and demultiplexer with all-metal compensating rod for...

Area of Science:

• Photonics and Optical Engineering
• Telecommunications Technology
• Materials Science in Optics

Background:

• Arrayed-waveguide gratings (AWGs) are crucial for wavelength division multiplexing (WDM) in optical networks.
• Temperature-dependent spectral drift in AWGs limits their operational stability and performance.
• Existing athermalization techniques often involve complex structures or compromise spectral characteristics.

Purpose of the Study:

• To propose and demonstrate a novel, compact device capable of functioning as both a multiplexer and demultiplexer.
• To achieve a flat-top spectral profile in an athermal arrayed-waveguide grating (AWG) module.
• To ensure ultra-wide temperature range operation with minimal spectral shift and insertion loss.

Main Methods:

• Design and fabrication of a unique all-metal compensating rod structure for the AWG chip.
• Integration of the compensating rods to achieve a spectrum profile nearly identical to the original chip.
• Characterization of the fabricated 100-GHz × 40-channel AWG module's performance over an ultra-wide temperature range.

Main Results:

• Successful fabrication of a flat-top athermal arrayed-waveguide grating module (100-GHz × 40-ch).
• Achieved a minimal center wavelength shift of ±25 pm over an ultra-wide temperature range (-40°C to 85°C).
• Demonstrated low insertion loss change of less than ±0.14 dB across the specified temperature range.

Conclusions:

• The proposed unique device effectively functions as both a multiplexer and demultiplexer.
• The all-metal compensating rod design enables a flat-top athermal AWG with excellent temperature stability.
• This technology offers a promising solution for robust and high-performance optical communication systems operating under extreme temperature conditions.