Microchip laser mid-infrared supercontinuum laser source based on an As2Se3 fiber

Area of Science:

• Optics and Photonics
• Laser Technology
• Materials Science

Background:

• Mid-infrared (MIR) supercontinuum sources are crucial for various applications, including spectroscopy and sensing.
• Existing technologies like periodically poled lithium niobate (PPLN) face limitations in power handling and spectral range.
• There is a need for compact, high-brightness MIR sources with extended wavelength coverage.

Purpose of the Study:

• To demonstrate a proof of concept for a compact supercontinuum source in the mid-infrared wavelength range.
• To utilize a novel selenide-based optical fiber for nonlinear wavelength conversion.
• To achieve broad spectral coverage beyond the limitations of current technologies.

Main Methods:

• A microchip laser was employed as the seed source.
• Nonlinear wavelength conversion was performed within the core of a single-mode selenide-based optical fiber.
• Spectral characterization was conducted to determine the supercontinuum's extent.

Main Results:

• The supercontinuum source demonstrated a spectrum from 3.74 to 4.64 μm at -10 dB and 3.65 to 4.9 μm at -20 dB.
• The generated spectrum extends beyond the usable range of periodically poled lithium niobate (PPLN).
• A maximum average output power of 5 mW was achieved, with a scalable architecture.

Conclusions:

• A compact and high-brightness mid-infrared supercontinuum source was successfully demonstrated.
• The use of selenide-based optical fiber enables efficient nonlinear conversion for extended spectral generation.
• This technology holds promise for scalable, high-power MIR applications.