Synthesis and luminescence properties of erbium silicate thin films

We have studied the structure and the room temperature luminescence of erbium silicate thin films deposited by rf magnetron sputtering. Films deposited on silicon oxide layers are characterized by good structural properties and excellent stability. The optical properties of these films are strongly improved by rapid thermal annealing processes performed in the range of temperature 800-1250 °C. In fact through the reduction of the defect density of the material, a very efficient room temperature photoluminescence at 1535 nm is obtained. We have also investigated the influence of the annealing ambient, by finding that treatments in O2 atmosphere are significantly more efficient in improving the optical properties of the material with respect to processes in N2. Upconversion effects become effective only when erbium silicate is excited with high pump powers. The evidence that all Er atoms (about 1022 cm-3) in erbium silicate films are optically active suggests interesting perspectives for optoelectronic applications of this material. © 2007 Elsevier B.V. All rights reserved.

Top Management Involvement in New Product Development: A Review and Synthesis

Established literature on new product development (NPD) management recognizes top management involvement (TMI) as one of the most critical success factors. With increasing pressure to sustain competitive advantage and growth, NPD activities remain the focus of close interest from top management in many organizations. TMI in the NPD domain is receiving increasing academic attention. Despite its criticality, there is no systematic review of the existing literature to inform and stimulate researchers in the field for further investigation. This paper introduces the current state of literature on TMI in NPD, synthesizes important findings, and identifies the gaps and deficiencies in this research stream. The contents of the selected articles, which investigated TMI in NPD, are analyzed based on the type of the study, level of analysis, research methodology, operationalization of TMI, and main findings. Additionally, other studies, which did not directly investigate TMI and support in NPD, but were sufficiently related, are briefly summarized. As a result of this detailed literature review, it can be stated that both exploratory and relational studies provide rich evidence on the critical role of top management in NPD. However, the identified gaps and deficiencies in this research stream call for a better theoretical understanding and well-defined constructs of TMI in the NPD domain for different levels of analysis for future studies.