All-optical switching using nonlinear subwavelength Mach-Zehnder on silicon

Area of Science:

• Photonics
• Optical Engineering
• Nonlinear Optics

Background:

• All-optical switching and wavelength conversion are crucial for advanced optical communication systems.
• Existing periodic waveguides often rely on resonant behavior, limiting their applicability.
• Subwavelength grating waveguides offer an alternative confinement mechanism without optical resonance.

Purpose of the Study:

• To experimentally demonstrate ultrafast all-optical switching.
• To achieve wavelength down-conversion using a novel nonlinear Mach-Zehnder interferometer.
• To implement a new method for all-optical switching control.

Main Methods:

• Fabrication of a nonlinear Mach-Zehnder interferometer incorporating subwavelength grating and wire waveguides.
• Utilizing the unique light confinement properties of subwavelength grating waveguides.
• Developing and implementing a novel approach for all-optical switching control.

Main Results:

• Successful experimental demonstration of ultrafast all-optical switching.
• Achieved wavelength down-conversion functionality.
• Validated a new strategy for all-optical switching control without dedicated input ports.

Conclusions:

• The novel nonlinear Mach-Zehnder interferometer with subwavelength gratings is effective for all-optical switching and wavelength down-conversion.
• The implemented all-optical switching control method is efficient and does not require dedicated optical signal input.
• This technology holds promise for future integrated photonic devices and optical signal processing.