Fast and bright spontaneous emission of Er(3+) ions in metallic nanocavity.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 25940839.
- Also identified by DOI 10.1038/ncomms8080 and PMC identifier 4432579.
- Licence recorded as CC BY.
- The licence permits redistribution, so the abstract is shown in full and the full text is available from the publisher.
Abstract
By confining light in a small cavity, the spontaneous emission rate of an emitter can be controlled via the Purcell effect. However, while Purcell factors as large as ∼10,000 have been predicted, actual reported values were in the range of about 10-30 only, leaving a huge gap between theory and experiment. Here we report on enhanced 1.54-μm emission from Er(3+) ions placed in a very small metallic cavity. Using a cavity designed to enhance the overall Purcell effect instead of a particular component, and by systematically investigating its photonic properties, we demonstrate an unambiguous Purcell factor that is as high as 170 at room temperature. We also observe >90 times increase in the far-field radiant flux, indicating that as much as 55% of electromagnetic energy that was initially supplied to Er(3+) ions in the cavity escape safely into the free space in just one to two optical cycles.