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Phase conjugation based on single backward second-order nonlinear parametric process
1Department of Electrical and Computer Engineering, Lehigh University, Bethlehem, Pennsylvania 18015, USA. yud2@lehigh.edu
Optics Letters
|November 21, 2012
Summary
This study demonstrates efficient phase conjugation using backward difference-frequency generation in nonlinear media. High nonlinear reflectivity near 100% is achievable with low-power lasers and cavity enhancement.
Area of Science:
- Nonlinear Optics
- Quantum Optics
Background:
- Phase conjugation is crucial for correcting optical aberrations.
- Traditional methods often require complex setups or high laser powers.
Purpose of the Study:
- To investigate backward difference-frequency generation for efficient phase conjugation.
- To explore broadband quasi-phase-matching in a backward configuration.
- To achieve high nonlinear reflectivity using low-power lasers.
Main Methods:
- Utilizing backward difference-frequency generation in a second-order nonlinear medium.
- Implementing a backward configuration for quasi-phase-matching.
- Placing the nonlinear medium inside a pump laser cavity.
- Employing a Fabry-Perot resonator to enhance nonlinear reflectivity.
Main Results:
- Demonstrated phase conjugation via backward difference-frequency generation.
- Achieved broadband quasi-phase-matching.
- Calculated near 100% nonlinear reflectivity with ~1 mW laser power.
- Showcased significant improvement in nonlinear reflectivity using a Fabry-Perot resonator.
Conclusions:
- Backward difference-frequency generation offers an efficient route to phase conjugation.
- The proposed method enables broadband quasi-phase-matching.
- Cavity enhancement and Fabry-Perot resonators are key to achieving high reflectivity with low-power lasers.
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