Abstract
The luminescence spectrum of MgO: is characterized by a series of sharp features at around 7000 Å and a broad band which stretches from about 7000 Å to 1 μm. The nature of the centers responsible for this broadband luminescence is examined by a combination of phase-sensitive detection methods and polarized absorption and luminescence methods. The phase-sensitive detection method allows us to separate clearly the broadband luminescence from the remainder of the spectrum and a sharp no-phonon line associated with the broadband luminescence is uncovered. The centers responsible for the broadband luminescence are found to have axes of symmetry along [011]-type directions, supporting the conclusion that this luminescence originates on ions in rhombic centers. At high temperatures broad emission is also observed from cubic site ions. The cubic site luminescence is shown to behave in accordance with theoretical expectations.
- Received 22 September 1975
DOI:https://doi.org/10.1103/PhysRevB.13.1893
©1976 American Physical Society