High Power Spark Delivery System Using Hollow Core Kagome Lattice Fibers

Area of Science:

• Optics and Photonics
• Materials Science
• Laser Technology

Background:

• Photonic Crystal Fibers (PCFs) are crucial for laser applications.
• Hollow core kagome lattice fibers offer unique properties for light manipulation.
• High power laser delivery faces challenges in energy coupling and beam quality.

Purpose of the Study:

• To investigate the potential of hollow core kagome lattice fibers for high power laser pulse delivery.
• To determine the maximum deliverable laser pulse energy as a function of pulse duration.
• To identify fiber damage mechanisms during high power laser transmission.

Main Methods:

• Utilized a Nd:YAG laser at 1064 nm for pulse delivery.
• Employed hollow core kagome lattice fibers with a ~50 µm core diameter.
• Analyzed laser pulse energy, duration, beam quality (M²), and fiber damage.

Main Results:

• Achieved transmission of 30 mJ pulse energy with 30 ns pulse durations.
• Maintained high beam quality at the output (M² = 1.25).
• Identified two primary fiber damage mechanisms: input and bulk damage.

Conclusions:

• Hollow core kagome lattice fibers enable record-high laser pulse energy delivery via PCFs.
• These fibers maintain excellent beam quality even at high energy levels.
• Demonstrated practical application through successful fiber-delivered laser ignition in an engine.