Efficient violet upconversion signal from a fluoride fiber doped with erbium

Area of Science:

• Materials Science
• Photonics
• Spectroscopy

Background:

• Upconversion luminescence in rare-earth-doped materials is crucial for various photonic applications.
• Erbium-doped fluoride fibers are investigated for their potential in optical devices.
• Understanding excitation mechanisms is key to controlling and optimizing upconversion emission.

Purpose of the Study:

• To investigate the upconversion emission properties of erbium-doped fluoride fiber.
• To identify the underlying excitation process responsible for observed emission.
• To compare the efficiency of violet and green upconversion emissions.

Main Methods:

• Pumping an erbium-doped fluoride fiber with a red dye laser.
• Resonant excitation of the erbium (4)F(9/2) state.
• Spectroscopic detection and analysis of upconversion emission.

Main Results:

• Efficient violet upconversion emission from the erbium (2)P(3/2) state was detected.
• Violet emission was significantly stronger than the green upconversion emission from the (4)S(3/2) state.
• The observed violet emission is attributed to a three-photon excitation process.

Conclusions:

• A three-photon excitation process can lead to efficient violet upconversion in erbium-doped fluoride fibers.
• This finding offers new possibilities for manipulating upconversion pathways and enhancing specific emission colors.
• The study highlights the potential for novel photonic applications utilizing strong violet emission.