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Updated: May 31, 2026
09:23
Quantum State Engineering of Light with Continuous-wave Optical Parametric Oscillators
Published on: May 30, 2014
Mid-IR frequency comb source spanning 4.4-5.4 μm based on subharmonic GaAs optical parametric oscillator
K L Vodopyanov1, E Sorokin, I T Sorokina
1E. L. Ginzton Laboratory, 348 via Palou, Stanford University, Stanford, California 94305, USA. vodopyan@stanford.edu
Optics Letters
|June 21, 2011
Summary
A novel degenerate subharmonic optical parametric oscillator (OPO) generated broadband mid-infrared output. This system is suitable for creating wide frequency combs, advancing mid-IR laser technology.
Area of Science:
- Nonlinear Optics
- Laser Physics
- Materials Science
Background:
- Frequency combs are crucial for precise measurements and spectroscopy.
- Generating broadband mid-infrared (mid-IR) light is challenging but essential for various applications.
- Optical parametric oscillators (OPOs) are versatile sources for generating tunable and broadband coherent light.
Purpose of the Study:
- To achieve broadband mid-IR output for generating wide frequency combs.
- To demonstrate the capability of a degenerate subharmonic OPO for mid-IR generation.
- To explore the use of orientation-patterned GaAs in mid-IR OPOs.
Main Methods:
- Utilized a degenerate subharmonic optical parametric oscillator (OPO).
- Employed a 500-μm-long Brewster-angled orientation-patterned Gallium Arsenide (GaAs) crystal.
- Synchronously pumped the OPO with femtosecond pulses (100 fs) from a Cr²⁺:ZnSe laser at 2.45 μm wavelength and 182 MHz repetition rate.
Main Results:
- Achieved broadband mid-IR output centered at 4.9 μm.
- Generated a 1000-nm-wide frequency comb.
- Demonstrated efficient parametric down-conversion in orientation-patterned GaAs.
Conclusions:
- The developed degenerate subharmonic OPO is effective for generating broadband mid-IR light.
- Orientation-patterned GaAs is a suitable material for mid-IR OPO applications.
- The system shows promise for applications requiring wide mid-IR frequency combs.
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