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Updated: Jun 26, 2025
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Measurement of Coherence Decay in GaMnAs Using Femtosecond Four-wave Mixing
Published on: December 3, 2013
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Phase Transitions and Nonlinear Optical Property Modifications in BaGa4Se7
Lyudmila Isaenko1, Linfeng Dong2, Svetlana V Melnikova3
1Sobolev Institute of Geology and Mineralogy SB RAS, Novosibirsk State University, Novosibirsk 630090, Russia.
Inorganic Chemistry
|May 15, 2024
Summary
BaGa4Se7 crystals exhibit a phase transition at 528 K, creating a new phase with enhanced middle infrared nonlinear optical properties. This structural change improves optoelectronic performance for mid-IR applications.
Area of Science:
- Solid-state physics
- Crystallography
- Materials science
Background:
- Phase transitions alter crystal structure and physical properties.
- BaGa4Se7 is a significant middle infrared (mid-IR) nonlinear optical (NLO) crystal.
Purpose of the Study:
- Investigate phase transition behavior in BaGa4Se7 from room temperature to 1173 K.
- Characterize the NLO properties of the newly discovered high-temperature phase.
Main Methods:
- Experimental study of temperature-dependent optical birefringence.
- First-principles calculations of birefringence and NLO coefficients.
Main Results:
- BaGa4Se7 undergoes a reversible ferroelastic phase transition at 528 K.
- A new gamma-phase emerges at higher temperatures.
- The gamma-phase shows increased birefringence and superior NLO properties compared to the alpha-phase.
Conclusions:
- Phase-transition-induced modifications enhance mid-IR NLO properties in BaGa4Se7.
- This offers a strategy for developing materials with improved optoelectronic performance.
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