Nonlinear switching in fibre Bragg gratings

Area of Science:

• Nonlinear optics
• Photonics
• Optical device physics

Background:

• Fiber Bragg gratings (FBGs) are crucial optical components.
• Nonlinear optical effects in FBGs are key for advanced functionalities.
• Controlling light propagation at high powers is essential for optical signal processing.

Purpose of the Study:

• To investigate and demonstrate high-power nonlinear switching in FBGs.
• To explore the formation of gap solitons and their role in optical switching.
• To develop an all-optical AND gate utilizing these nonlinear phenomena.

Main Methods:

• Utilized an all-fibre light source for high-power experiments.
• Fabricated and tested fiber Bragg gratings.
• Employed polarization-coupled gap solitons and optical pushbroom techniques.

Main Results:

• Achieved a significant increase in FBG transmission from 4% to 40% at high optical powers.
• Observed the formation of gap solitons within the grating structure, confirming their role in switching.
• Successfully demonstrated an all-optical AND gate functionality.

Conclusions:

• Nonlinear switching in FBGs is feasible and can be significantly enhanced at high powers.
• Gap solitons are fundamental to achieving high transmission increases and enabling all-optical logic gates.
• The demonstrated AND gate represents a significant step towards practical all-optical signal processing and computing.