NOWAL · Nanocluster-sensitised optical waveguide amplifiers and lasers
FP6 — Marie Curie Actions (Human Resources and Mobility)
- Duration
- 2007-05-01 → 2009-04-30
- EU contribution
- €159,613
- Participants
- 1
- Scheme
- EIF
Lines connect the coordinator with its partners.
Results in brief
Final Activity Report Summary - NOWAL (Nanocluster-sensitised optical waveguide amplifiers and lasers)
In this project, the viability of an erbium-doped laser or amplifier indirectly pumped through silicon nanoclusters has been studied. This optical pumping scheme would dramatically decrease the cost of these devices because the pump device would be subject to much less constraints, thus it would have an impact in the telecommunications industry. At the end of the project, the indirectly pumped laser or amplifier has not been demonstrated yet. However, the project has produced important contributions towards the understanding of the material, and towards ways to overcome some unexpected technical difficulties that have been encountered. Regarding the material understanding, a model has been proposed for the energy transfer mechanism from the nanoclusters to the Er. A distant dependent model explains many experimental observations and also the difficulties to indirectly excite a high population fraction, providing some strategies that would lead to a more efficient excitation. On the other hand, problems associated with the stress in the films during annealing have been investigated, and a solution consisting of annealing the layer after etching the ribs has been proposed and proved to be successful. Finally, the ultimate issues preventing the observation of net gain in these waveguides have been identified. The main difficulties were found to be: (i) the propagation loss, which was found to be around 3 dB/cm, which is comparable to the expected gain, making net gain difficult; (ii) the difficulty of indirectly exciting a high ratio of Er population, due to the distance dependent interaction between nanoclusters and Er.
Data: CORDIS, © European Union
Project objective
The goal of this proposal is to assess the viability of silicon-sensitised erbium doped materials systems for optical device applications. Our work will focus on silicon nanoclusters of 2-4nm diameter that possess novel optical properties, including the ability to efficiently transfer optical excitation to nearby luminescent species. We aim to exploit the optical sensitisation effects of these nanoclusters, which allow us to couple into Er ions far more effectively than is possible in conventional rare ear th-doped glasses. The broad absorption spectrum of the nanoclusters and their very large excitation cross-section will enable us to develop planar optical devices that are pumped in a top down configuration using cheap broad-band sources such as LEDs.Compared to the expensive lasers currently used, we stand to achieve a potential 100-fold reduction in pump power costs by deploying LEDs instead, opening the door for such devices to find applications in local area networks. An amplifier in a waveguide geometry can also allow the fabrication of complex integrated optical circuits, and combine them with silicon technology to achieve electro-optical signal conversion. The erbium-doped silicon-rich silica material will be first characterised and the transfer mechanism will be studied; the fabrication parameters will be varied in order to optimise the efficiency and reduce possible excited state absorption processes. Then, channel waveguides will be characterised (optical gain, scattering, absorption...) under different pumping conditions. The final aim of the project is to demonstrate LED-pumped waveguide amplifiers and lasers in the 1.5 micron range.
Original text from CORDIS.
Participants
- UNIVERSITY OF SOUTHAMPTON · SOUTHAMPTONCoordinatorUnited Kingdom
Links
Data: CORDIS, © European Union