| Article ID | Journal | Published Year | Pages | File Type |
|---|---|---|---|---|
| 7908560 | Optical Materials | 2016 | 5 Pages |
Abstract
We report on the size dependent photoresponse behaviour of crystalline Ge quantum dots (QDs) dispersed within the silica matrix. Our findings demonstrate an increasing nature of EQE with increase in QDs size, which could be attributed to the combined effect of Coulomb interaction of photogenerated carriers, QD/silica interface defects and electric field driven carrier separation and tunneling through the oxide barriers. In this regard, the bias dependent nonlinear response of the photocurrent has been explained on the basis of cold field emission (CFE) model. Besides, the EQE is extended (>100%) for larger sized QDs, suggesting the trapping of slower holes in Ge QDs creating a charge neutrality issue.
Related Topics
Physical Sciences and Engineering
Materials Science
Ceramics and Composites
Authors
Rajshekhar Bar, Santanu Manna, Samit K. Ray,