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Updated: Jun 3, 2026
06:42
Generation and Coherent Control of Pulsed Quantum Frequency Combs
Published on: June 8, 2018
Efficiency pedestal in quasi-phase-matching devices with random duty-cycle errors.
J S Pelc1, C R Phillips, D Chang
1E L Ginzton Laboratory, Stanford University, Stanford, California 94305, USA. jpelc@stanford.edu
Optics Letters
|March 16, 2011
Summary
Random errors in quasi-phase-matching (QPM) nonlinear optical devices unexpectedly boost efficiency for processes distant from the QPM peak. This finding is crucial for optimizing QPM device performance and minimizing unwanted interactions.
Area of Science:
- Nonlinear Optics
- Materials Science
Background:
- Quasi-phase-matching (QPM) is essential for efficient nonlinear optical processes.
- Disorder in QPM gratings can negatively impact device performance.
Purpose of the Study:
- To investigate the effect of random duty-cycle errors in QPM devices.
- To analyze how these errors influence efficiency, particularly away from the QPM peak.
Main Methods:
- Developed an analytical theory for disordered QPM gratings.
- Performed numerical solutions for second-harmonic generation (SHG).
- Measured 1550 nm band SHG efficiency in periodically poled lithium niobate (PPLN) waveguides.
Main Results:
- Random duty-cycle errors enhance efficiency for processes far from the QPM peak.
- Analytical theory shows good agreement with numerical SHG solutions.
- Experimental measurements of SHG efficiency in PPLN align with theoretical predictions.
Conclusions:
- Random duty-cycle errors can be beneficial in specific QPM applications.
- Controlling these errors is critical for suppressing parasitic nonlinear interactions.
- Understanding disorder effects is key for designing advanced QPM devices.
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