Single-pass UV generation at 222.5 nm based on high-power GaN external cavity diode laser

Area of Science:

• Optics and Photonics
• Materials Science
• Laser Physics

Background:

• Deep ultraviolet (UV) light sources are crucial for various scientific and industrial applications.
• Existing deep UV generation methods often involve complex and bulky systems.
• Gallium Nitride (GaN) diode lasers offer a promising platform for compact and efficient light sources.

Purpose of the Study:

• To demonstrate a compact, diode laser-based system for generating deep UV radiation.
• To achieve efficient frequency doubling of high-power GaN diode laser output.
• To explore the potential of beta-barium borate (BBO) crystals for deep UV generation.

Main Methods:

• Utilized a high-power GaN external cavity diode laser (ECDL) operating at 445 nm as the pump source.
• Employed a single-pass frequency doubling configuration.
• Used a beta-barium borate (BBO) crystal to convert the fundamental laser wavelength to deep UV.

Main Results:

• Successfully generated deep UV laser light at 222.5 nm.
• Achieved a maximum UV power of 16 μW under continuous-wave operation.
• Demonstrated efficient frequency doubling with a pump power of 680 mW.

Conclusions:

• A compact and efficient system for deep UV generation using GaN diode lasers has been successfully demonstrated.
• This technology paves the way for portable and accessible deep UV light sources.
• The use of BBO crystals in conjunction with GaN ECDLs is effective for generating 222.5 nm radiation.