Nonlinear Optics

Q-Peak expands the wavelength capability of our solid-state and fiber lasers by developing and constructing wavelength conversion modules based on nonlinear optical techniques. They include harmonic and parametric generators, parametric oscillators and amplifiers, and sum frequency generation (SFG). Typically, second-, third-, and fourth-harmonic generators (SHG, THG, and FHG, respectively) shift the fundamental laser wavelength to shorter, discrete wavelengths, whereas the parametric conversion allows for covering longer wavelengths and broad-band tuning.

Red-Green-Blue OPO Nonlinear Optics

OPO experimental setup showing simultaneous red, green, and blue generation

Examples of our technologies include but not limited to:

  • Consistently high, up to 60 percent external SHG conversion efficiencies from 1047 nm to 523 nm
  • High-energy tunable SHG, SFG, THG and FHG from Ti:sapphire lasers
  • Intracavity SHG, THG, and FHG generation of 1-micron lasers with up to 75% conversion efficiency
  • High-efficiency, broadly tunable Tandem KTA/CdSe OPO designs capable of covering four bands in the spectral range from 1.5 to 12 microns;
  • Single-frequency output from a seeded, high-pulse-energy KTA OPO
  • Tunable, galvo-controlled BBO OPO pumped by a 355-nm source with a rapid and random wavelength agility within a 420- 600-nm band and a switching speed of 2.5 ms/0.1 nm.


Q-Peak incorporates a large range of nonlinear materials into advanced optical assemblies and laser systems:
Critically and non-critically phase-matched crystalline materials: KTP (Potassium Titanyl Phosphate, KTiOPO4,) and its isomorphs, KTA (Potassium Titanyle Arsenate, KTiOAsO4,) and RTP (Rubidium Titanyle Phosphate, RbTiOPO4); LBO (Lithium Triborate, LiB3O5); BBO (Beta-Barium Borate, β-BaB2O4); KDP and KD*P (Potassium Dihydrogen Phosphate and Potassium Dideuterium Phosphate) We also utilize quasi-phase-matched materials such as Periodically Poled Lithium Niobate (PPLN) and orientation-patterned GaAs (OP-GaAs).


Our nonlinear devices and/or systems cover discrete wavelengths in UV and VIS ranges: 262 nm, 266 nm, 349 nm, 355 nm, 523 nm, 532 nm. We also have an expertise in building tunable UV and VIS sources in the 220 nm - 600 nm range. In mid- and long-wavelength infra-red (MWIR and LWIR) ranges we have constructed tunable sources from 1.5 microns to 12 microns.


  • Aerospace and Defense
  • Space Missions
  • Materials Processing
  • Laser Communications
  • Scientific Research
  • Medical Lasers
  • Sensors and Instruments

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