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Theoretical Calculation and Experimental Verification for Dislocation Reduction in Germanium Epitaxial Layers with Semicylindrical Voids on Silicon
Published on: July 17, 2020
Multiline phase conjugation at 4 microm in germanium
1Air Force Weapons Laboratory. Kirtland Air Force Base, New Mexico 87117, USA.
Optics Letters
|August 21, 2009
Summary
Researchers achieved phase conjugation using degenerate four-wave mixing in germanium. This nonlinear optical process demonstrated efficient phase conjugation for both single-line and multiline laser outputs.
Area of Science:
- Nonlinear optics
- Condensed matter physics
- Laser physics
Background:
- Degenerate four-wave mixing (DFWM) is a nonlinear optical process used for phase conjugation.
- Germanium is a semiconductor material with potential for nonlinear optical applications in the infrared region.
Purpose of the Study:
- To investigate phase conjugation via DFWM in germanium at a 4-micrometer wavelength.
- To measure the third-order nonlinear susceptibility (X3) for single-line laser output.
- To evaluate the efficiency of phase conjugation for multiline laser output.
Main Methods:
- Utilizing a deuterium fluoride (DF) laser with single-line output at 3.8 micrometers.
- Performing degenerate four-wave mixing experiments in a germanium medium.
- Measuring the nonlinear optical response and phase conjugation efficiency.
Main Results:
- Observed phase conjugation in germanium for both single-line and multiline laser radiation.
- Measured the third-order nonlinear susceptibility (X3) to be 4 x 10^-1 esu for single-line output.
- Achieved a phase conjugation efficiency of 0.03% for multiline laser output.
Conclusions:
- Demonstrated the feasibility of phase conjugation in germanium using DFWM in the 4-micrometer region.
- The results for multiline output are consistent with the single-line susceptibility, suggesting independent conjugation of each line.
- Germanium shows promise for nonlinear optical applications involving phase conjugation of infrared radiation.
