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Fabrication And Characterization Of Photonic Crystal Slow Light Waveguides And Cavities
Published on: November 30, 2012
Enhanced nonlinear Cherenkov radiation on the crystal boundary
Huaijin Ren1, Xuewei Deng, Yuanlin Zheng
1Department of Physics, Key Laboratory for Laser Plasmas Ministry of Education Shanghai Jiao TongUniversity, 800 Dongchuan Road, Shanghai 200240, China.
Optics Letters
|June 1, 2013
Summary
Researchers developed a new method to enhance nonlinear Cherenkov radiation (NCR) in crystals using total internal reflection. This technique offers improved beam quality for practical applications.
Area of Science:
- Nonlinear optics
- Condensed matter physics
- Materials science
Background:
- Nonlinear Cherenkov radiation (NCR) is a significant phenomenon in nonlinear optics.
- Existing methods for enhancing NCR often rely on specific structures like waveguides or ferroelectric domain walls.
- Achieving enhanced NCR with superior beam quality is crucial for various applications.
Purpose of the Study:
- To demonstrate a novel method for generating enhanced nonlinear Cherenkov radiation (NCR) within a bulk medium.
- To experimentally validate the enhancement of NCR through sharp modulation of the nonlinear susceptibility χ(2).
- To introduce a new approach for NCR enhancement beyond conventional waveguide and domain wall techniques.
Main Methods:
- Utilizing total internal reflection at physical boundaries within a crystal.
- Implementing a sharp modulation of the second-order nonlinear susceptibility (χ(2)) from 0 to 1.
- Experimental generation and characterization of enhanced NCR.
Main Results:
- Successful demonstration of enhanced nonlinear Cherenkov radiation (NCR) in a bulk medium.
- Observation of NCR enhancement directly linked to the sharp χ(2) modulation.
- The method yields NCR with improved beam quality compared to previous techniques.
Conclusions:
- Total internal reflection provides an effective mechanism for enhancing NCR in bulk media.
- This sharp χ(2) modulation technique represents a new and viable pathway for generating enhanced NCR.
- The enhanced NCR produced exhibits superior beam quality, making it suitable for advanced applications.
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