Materials Processing / Spectroscopy

Q-Peak has developed multiple laser sources for Materials Processing and Spectroscopy Research and Development for both Defense and Commercial applications. Most recently Q-Peak developed an Ultrafast UV laser system for deep micro-drilling materials processing applications. Starting with Ytterbium based femtosecond regenerative amplifier, Q-Peak developed a third and fourth harmonic generator for a few Watts at 350nm and 260nm performance. The full laser system is shown below.

UV Femtosecond Laser
UV Femtosecond Laser Source

Spectroscopy applications range from under the sea to the far reaches of space, whether probing atmosphere, gases, or materials for chemical composition. Techniques such as Laser Induced Breakdown Spectroscopy (LIBS) have recently demonstrated the ability to detect and discriminate chemical, biological, and explosives hazards both in close-contact and standoff modes. Currently the LIBS devices that have been and are being developed for field use are based on nanosecond lasers and have certain limitations that can be overcome through the use of femtosecond lasers. However, to date, femtosecond lasers have been too large, bulky, delicate, and expensive to be considered as viable candidates for field use. Our technical approach to a previous challenging program was to develop a compact, high-power, diode-pumped, Yb:doped femtosecond oscillator- regenerative amplifier laser system. A schematic of the system design appears below. In the program:

  • We determined the optimal laser material choice for both diode-pumped oscillator and regenerative amplifier in order to achieve the targeted output specifications.

  • We built and characterized the performance of a compact, ruggedized diode-pumped Yb:doped femtosecond oscillator.

  • We built and characterized the performance of diode-pumped, Yb:doped regenerative amplifier.

  • We conducted amplification experiments to evaluate the efficiency of regenerative amplification. We designed and built a novel, compact, pulse stretcher/compressor based on a chirped volume Bragg grating from Optigrate to achieve a sub-ps pulse duration from the amplifier output. We conducted spectral-temporal characterization of the output of the Yb:doped laser system.

  • We integrated the femtosecond oscillator, regenerative amplifier and stretcher/compressor pair into a compact and robust configuration as a stand-alone, ultrafast, high-power, compact laser source.
  • We conducted a set of laboratory experiments to demonstrate the applicability of the laser system for LIBS.

Overall, the program was successful and resulted in the construction of a compact, 1.8 mJ pulse energy, 600 fs oscillator-regenerative amplifier Yb:doped laser system suitable for LIBS. The high peak power of the system (3 GW) should make it suitable for a variety of applications beyond LIBS.

Assembled Laser Head
Assembled laser head