Liquid-Cooled Disk Modules

Aqwest liquid-cooled disk laser gain modules offer operation at higher pulse repetition rate and average power. The liquid-cooled EPDL modules are operable at 1 or 2 micron wavelength depending on the choice of laser gain material and pump diodes. Current aperture sizes range from 12.5 to 27 mm and stored energy from 1 to 5 Joules.

We developed the original flat EPDL module for the US Army in 2011 and operated 2 modules in a multi-pass amplifier in 2013. A self-contained version of the multi-pass amplifier was developed for the U.S. DOE in recent years. 

To attain higher pulse energies and average power requires an amplifier with multiple modules. To package multiple modules into a scalable amplifier, we designed a new laser disk amplifier module (dubbed Module C) with universal architecture that supports broadband amplification at each 1 and 2 micron wavelengths, a range of aperture sizes, and stored pulse energies up to 5 Joules. The new laser module is self-contained and remarkably compact, which allows convenient integration of multiple modules into a very powerful amplifier used for short and ultra-short pulse lasers (latter being also known as ultrafast lasers or UFL). Module C is operable at high-pulse energy and high-pulse repetition rate need for the generation and heating of high-density energy plasmas now being pursued worldwide as a part of the “second laser revolution.” Other applications include commercial laser material processing such as cutting, drilling, and welding. When operated at 2 micron wavelength, Module C is 100-times eye-safer that the commonly used 1-micron wavelength lasers. The compact  EPDL produced first laser light in April 2022. This project is supported by the US Department of Energy (DOE).

References

  1. Vetrovec, D.A. Copeland, D. Du, and B. Schmidt “Ytterbium–Based Disk Amplifier for an Ultra–Short Pulse Laser,” Proc. of SPIE 7578, 2010
  2. Drew A. Copeland, “Optical Extraction Model and Optimal Outcoupling for a CW Quasi-Three Level Thin Disk La­ser,” in SPIE Vol. 7912, 2011
  3. A. Copeland and J. Vetrovec, “Gain tailoring model and improved optical extraction in CW edge-pumped disk amplifiers,” SPIE vol. 8235-24, January 2012
  4. Vetrovec, D. A. Copeland, D. Du, and B. Schmidt, “Initial testing of edge-pumped Yb:YAG disk laser with multi-passed extraction,” SPIE vol. 8235-23, January 2012
  5. Vetrovec, D. A. Copeland, A. Litt, and D. Du, “ Erbium-Based Edge-Pumped Disk Laser,” SPIE Paper  8599-61 (2013)
  6. Vetrovec, D. Copeland, A. Litt, and D. Du, ““Initial testing of edge-pumped Yb:YAG disk laser with multi-passed extraction,” SPIE vol. 8235-23, January 2013
  7. Copeland and J. Vetrovec, “Gain Tailoring Model and Improved Optical Extraction in CW Edge–Pumped Disk Amplifiers,” SPIE vol 8235 (2012)
  8. Vetrovec and R. Clark, “High-gain solid-state laser,”, U.S. Patent No. 7,477,674, January 13, 2009
  9. Vetrovec, D. A. Copeland, A. S. Litt, and D. M. Filgas, “Lasing Performance of an Edge-Pumped Ceramic Yb:YAG Disk Laser with a Tailored Spatial Gain Profile,” SPIE vol. 10511, February 2018
  10. Vetrovec, D. Copeland, A. Litt, and D. Du, “High-gain Yb:YAG amplifier for ultrashort pulse laser at high-average power,” SPIE vol. 9726-44, February 2016
  11. Vetrovec, US Patent No. 6,625,193, 2003
  12. Vetrovec, D. A. Copeland, A. S. Litt, S. J. Thiagarajan, and E. Briscoe, “Stored Energy and Gain in an Edge-Pumped Ceramic Yb:YAG Disk Laser under Intense Pumping,” SPIE vol. 10084, 2017
  13. Vetrovec, “Disk lasers: Path to compact modular designs for high performance,” (Invited) SPIE vol. 10511, February 2020