Supercontinuum generation in strip/slot hybrid waveguide with flat and low dispersion

Area of Science:

• Photonics and Nanotechnology
• Integrated Optics
• Nonlinear Optics

Background:

• Achieving flat and low dispersion in optical waveguides is crucial for broadband signal transmission and supercontinuum generation.
• Traditional waveguide designs often struggle to maintain low dispersion over extended bandwidths, limiting their nonlinear applications.

Purpose of the Study:

• To propose and characterize a novel strip/slot hybrid waveguide with double horizontal silicon nanocrystal slots.
• To demonstrate the achievement of flat and low dispersion with multiple zero dispersion wavelengths.
• To investigate the potential for broadband supercontinuum generation in the near- and mid-infrared regions.

Main Methods:

• Design and simulation of a strip/slot hybrid waveguide incorporating double horizontal silicon nanocrystal slots.
• Systematic tuning of waveguide structural parameters to tailor dispersion characteristics.
• Numerical analysis of dispersion properties, including zero dispersion wavelengths and bandwidth.
• Simulation of supercontinuum generation pumped by a femtosecond laser pulse.

Main Results:

• The proposed waveguide exhibits flat dispersion ranging from -13 to 14 ps/(nm·km) over an 845 nm bandwidth.
• Four zero dispersion wavelengths were achieved through structural parameter optimization.
• A broadband supercontinuum spectrum spanning 1.15 to 3.65 μm (at -15 dB level) was generated.
• The waveguide was pumped by a femtosecond pulse at 1.86 μm.

Conclusions:

• The developed silicon nanocrystal waveguide effectively achieves flat and low dispersion, crucial for nonlinear optical applications.
• The demonstrated broadband supercontinuum generation highlights the waveguide's potential in near- and mid-infrared nonlinear photonics.
• This design offers a promising platform for advanced optical signal processing and light generation technologies.