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$Interference and Diffraction$ 02:18

Interference and Diffraction

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Optimized grating-frustrated coupler.

A Yesayan, R Vallée

|December 1, 2007

Summary

This summary is machine-generated.

A novel grating-frustrated coupler design eliminates backreflected light. This enhanced coupler efficiently directs all light near the Bragg wavelength to the designated drop port.

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Area of Science:

Photonics and optical engineering
Waveguide devices

Background:

Grating-based optical couplers are essential components in integrated photonics.
Minimizing backreflection and maximizing transmission are critical performance metrics for optical couplers.

Purpose of the Study:

To theoretically analyze a modified grating-frustrated coupler incorporating a second grating.
To demonstrate the capability of the proposed design to achieve zero backreflection and high transmission efficiency.

Main Methods:

Detailed theoretical analysis using coupled-mode theory.
Numerical simulations to validate the analytical predictions.

Main Results:

The addition of a second grating in the input channel effectively suppresses backreflected light to zero.
The modified coupler demonstrates near-unity transmission of light at the Bragg wavelength to the drop port.

Conclusions:

The proposed modified grating-frustrated coupler offers superior performance for optical signal routing.
This design presents a significant advancement for applications requiring efficient and clean light coupling.