Enhanced properties of the mid-infrared superluminescent emitter with a composite waveguide

Area of Science:

• Optoelectronics
• Quantum Cascade Lasers
• Mid-Infrared Photonics

Background:

• Superluminescent emitters are crucial for broadband light sources.
• Quantum cascade superluminescent emitters (QC-SLEs) offer unique mid-infrared capabilities.
• Enhancing spectral width and output power in QC-SLEs remains a key challenge.

Purpose of the Study:

• To design and investigate a composite structure for enhanced QC-SLE performance.
• To optimize waveguide geometry for broadband emission and high power.
• To explore the impact of tilted and curved waveguides on device characteristics.

Main Methods:

• Computational modeling of waveguide structures with varying tilt and curve angles.
• Fabrication and experimental characterization of optimized QC-SLE devices.
• Analysis of spectral width, output power, and reflectivity.

Main Results:

• A composite structure with 10° tilt and 20° curve angles minimized reflectivity.
• Minimized interference effects and reduced perpendicular mode propagation.
• Achieved experimental spectral width of 168.5 cm⁻¹ and output power of 5.1 mW.

Conclusions:

• The proposed composite waveguide design is a novel approach for broadband, high-power QC-SLEs.
• Optimized geometric parameters are critical for overcoming wavelength selectivity.
• This work paves the way for advanced mid-infrared superluminescent sources.