Directly diode-pumped Yb:KY(WO(4))(2) regenerative amplifiers

Area of Science:

• Laser physics
• Materials science

Background:

• Yb(3+)-doped KY(WO4)2 (ytterbium-doped potassium yttrium tungstate) is a promising gain medium for ultrafast lasers.
• Regenerative amplifiers are crucial for generating high-energy ultrashort laser pulses.

Purpose of the Study:

• To demonstrate and compare the performance of two Yb(3+)-doped KY(WO4)2 regenerative amplifiers with different pumping configurations.
• To investigate the feasibility of using end-pumping and side-pumping schemes for high-power ultrafast laser amplification.

Main Methods:

• Fabrication and characterization of two Yb(3+)-doped KY(WO4)2 regenerative amplifiers.
• One amplifier was end-pumped by two 1.6-W single-stripe diodes at 940 nm.
• The other amplifier was side-pumped by a 20-W diode bar at 980 nm.
• Pulses were compressed after amplification to achieve ultrashort durations.

Main Results:

• The end-pumped amplifier delivered 40-μJ, 400-fs pulses at a 1-kHz repetition rate after compression.
• The side-pumped amplifier delivered 65-μJ, 460-fs pulses at a 1-kHz repetition rate after compression.
• Both configurations demonstrated effective amplification of ultrashort pulses.

Conclusions:

• Yb(3+)-doped KY(WO4)2 is a versatile material for ultrafast regenerative amplifiers.
• Side-pumping configuration offers higher pulse energy compared to end-pumping for this specific setup.
• Further optimization of pumping schemes can lead to even higher performance in ultrafast laser systems.