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08:01
Spectral and Angle-Resolved Magneto-Optical Characterization of Photonic Nanostructures
Published on: November 21, 2019
First-principles optical spectra for F centers in MgO
Patrick Rinke1, André Schleife, Emmanouil Kioupakis
1Materials Department, University of California, Santa Barbara, California 93106, USA.
Physical Review Letters
|May 1, 2012
Summary
This study clarifies oxygen vacancy optical properties in MgO. Calculations show absorption and emission spectra for different charge states peak at similar energies, leading to a reinterpretation of F center behavior.
Area of Science:
- Materials Science
- Solid-State Physics
- Computational Chemistry
Background:
- Oxygen vacancies (F centers) in Magnesium Oxide (MgO) exhibit complex optical properties.
- Distinguishing between positively charged (F+) and neutral (F0) oxygen vacancies is challenging due to similar absorption energies.
Purpose of the Study:
- To accurately calculate and interpret the optical absorption and emission spectra of oxygen vacancies in all three charge states (including the doubly negative F2- center).
- To resolve the ambiguity in experimental optical spectra attributed to F0 and F+ centers.
- To provide a theoretical basis for reinterpreting the optical properties of F centers in MgO.
Main Methods:
- Utilizing many-body perturbation theory within the G0W0 approximation.
- Employing the Bethe-Salpeter equation approach for optical properties.
- Calculating optical absorption and emission spectra for F0, F+, and F2- charge states.
Main Results:
- Achieved unprecedented agreement between calculated and experimental optical absorption spectra for F0 and F+ centers.
- Demonstrated that absorption and emission spectra for different oxygen vacancy charge states peak at nearly identical energies.
- Provided theoretical insights into the electronic structure and optical transitions of oxygen vacancies.
Conclusions:
- The study successfully differentiates the optical spectra of various oxygen vacancy charge states in MgO.
- The findings necessitate a reevaluation of previous interpretations of F center optical properties based on experimental data.
- This work offers a robust theoretical framework for understanding point defect behavior in oxides.
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