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Methods of Ex Situ and In Situ Investigations of Structural Transformations: The Case of Crystallization of Metallic Glasses
Published on: June 7, 2018
Determining selected quadratic coefficients in noncentrosymmetric crystals
Mike Melnichuk1, Lowell T Wood
1Department of Physics, University of Houston, Texas 77204, USA.
Summary
Researchers theoretically explored measuring quadratic symmetry tensors in non-centrosymmetric solids. New methods bypass linear effects, enabling direct measurement of quadratic optical properties in crystals.
Area of Science:
- Solid-state physics
- Materials science
- Crystallography
Background:
- Non-centrosymmetric crystals exhibit unique optical properties due to their lack of inversion symmetry.
- Measuring quadratic effects, such as electro-optic and elasto-optic effects, is crucial for understanding material behavior.
- Linear optical effects often dominate, complicating the isolation and measurement of quadratic responses.
Purpose of the Study:
- To theoretically investigate the feasibility of measuring quadratic symmetry tensor components in solids lacking inversion symmetry.
- To develop and present methods for directly probing quadratic effects, bypassing dominant linear optical phenomena.
- To demonstrate the applicability of these methods to electro-optic and elasto-optic effects in non-centrosymmetrical crystals.
Main Methods:
- Systematic theoretical examination of measurement possibilities.
- Development of theoretical approaches to isolate quadratic effects from linear effects.
- Analysis of symmetry tensor components in the context of optical phenomena.
Main Results:
- Demonstrated the practical possibility of measuring quadratic symmetry tensor components in non-centrosymmetric materials.
- Established theoretical methods to bypass dominant linear effects for direct quadratic effect measurement.
- Confirmed the validity of the approach for both electro-optic and elasto-optic effects.
Conclusions:
- Direct measurement of quadratic symmetry tensors in non-centrosymmetric solids is theoretically achievable.
- The proposed methods offer a pathway to precisely characterize quadratic optical responses in relevant materials.
- These findings have implications for the study and application of electro-optic and elasto-optic phenomena in crystals.
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