Mechanism of Photoluminescence Quenching of InGaAs/GaAs Quantum Dots Resulting from Nanoprobe Indentation
Abstract:The low-temperature (10 K) photoluminescence (PL) of self-assembled InGaAs/GaAs quantum dots (QDs) was measured under the elastic indentation of a flat cylindrical nanoprobe that generates localized strain fields around itself. As the indentation force increases, the intensity of the PL fine peak from a single QD firstly increases, followed by a decrease, and is finally quenched. The observed force at which a PL peak disappears, i.e., the quenching force varies from QD to QD. This variation is ascribed to the diversely distributed strain fields in and around each QD and therefore can be related to the QD location with respect to the nanoprobe center. In order to clarify the mechanism of PL quenching, a numerical simulation of the strain distribution is carried out by a 3-dimensional finite element method. The modification of the energy band structure resulting from strain is then calculated based on the deformation potential theory. We concluded that the PL quenching observed experimentally can be attributed to the electron-repulsion resulting from the strain-induced potential gradient. Based on this mechanism, an indentation-induced shift of the electron-potential in bulk GaAs, at which the PL from QDs is quenched, was deduced to be 43.5–133.5 meV.
Document Type: Research Article
Publication date: 2011-01-01
More about this publication?
- Journal for Nanoscience and Nanotechnology (JNN) is an international and multidisciplinary peer-reviewed journal with a wide-ranging coverage, consolidating research activities in all areas of nanoscience and nanotechnology into a single and unique reference source. JNN is the first cross-disciplinary journal to publish original full research articles, rapid communications of important new scientific and technological findings, timely state-of-the-art reviews with author's photo and short biography, and current research news encompassing the fundamental and applied research in all disciplines of science, engineering and medicine.
- Editorial Board
- Information for Authors
- Subscribe to this Title
- Terms & Conditions
- Ingenta Connect is not responsible for the content or availability of external websites