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Assessment of Boron Doped Diamond Electrode Quality and Application to In Situ Modification of Local pH by Water Electrolysis
Published on: January 6, 2016
Revised fine splitting of excitons in diamond
1Abteilung Halbleiterphysik, Universitat Ulm, 89069 Ulm, Germany.
Physical Review Letters
|September 16, 2000
Summary
We observed new fine structure in synthetic diamond excitons using cathodoluminescence. This reveals a common doublet splitting, resolving previous discrepancies in free and bound exciton analysis.
Area of Science:
- Solid State Physics
- Materials Science
- Diamond Spectroscopy
Background:
- Synthetic diamonds produced under high pressure and temperature are crucial materials.
- Exciton emission in diamonds provides insights into electronic properties.
- Previous studies noted inequivalent fine splitting in free and bound excitons.
Purpose of the Study:
- To investigate the fine structure of free and boron-bound excitons in synthetic diamonds.
- To resolve discrepancies in previously reported exciton fine splitting values.
- To understand the fundamental electronic excitations in these diamond materials.
Main Methods:
- Low-strain synthetic diamond characterization.
- High-resolution cathodoluminescence spectroscopy.
- Analysis of exciton emission spectra.
Main Results:
- Observation of novel fine structure in both free exciton and boron-bound exciton emission.
- Identification of a common doublet spectral structure with a splitting of approximately 11 meV.
- Resolution of the inequivalence between free exciton (approx. 7 meV) and bound exciton (approx. 12 meV) fine splitting.
Conclusions:
- The observed common fine structure suggests a unified mechanism for exciton excitation.
- Spin-orbit interaction, smaller than excitonic binding and localization energies, leads to recoupling of orbital momentum and spin.
- Elementary excitations are formed as spin singlet and triplet exciton states.
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