High-energy mid-infrared Er,Pr:GYAP laser with LD side pumping

Area of Science:

• Laser Physics
• Materials Science

Background:

• Erbium-Praseodymium-doped Gadolinium Yttrium Aluminum Perovskite (Er,Pr:GYAP) lasers are explored for high-energy applications.
• Mid-infrared laser development requires efficient and robust gain media.

Purpose of the Study:

• To demonstrate a high-energy laser using Er,Pr:GYAP.
• To investigate its performance in free-running and electro-optically Q-switched operations.
• To analyze the impact of pump pulse width on conversion efficiency.

Main Methods:

• Utilized a laser-diode (LD) side-pumped configuration.
• Tested both bonded and unbonded Er,Pr:GYAP crystal rods.
• Operated the laser in free-running and Q-switched modes at various frequencies and pump pulse widths.

Main Results:

• Achieved maximum output energies of 1.21 J (bonded) and 0.94 J (unbonded) in free-running mode.
• Obtained a maximum pulse energy of 125 mJ with a 33.55 ns pulse width in Q-switched mode.
• Identified amplified spontaneous emission (ASE) as a significant factor reducing conversion efficiency with increased pump pulse width.

Conclusions:

• Er,Pr:GYAP is a viable gain medium for high-energy mid-infrared lasers.
• Optimizing pump pulse width is crucial to mitigate energy loss due to ASE.
• Bonded crystal rods show superior performance in free-running operation.