The doctoral dissertation in the field of Photonics will be examined at the Faculty of Science, Forestry and Technology, Joensuu campus.
What is the topic of your doctoral research? Why is it important to study the topic?
The research focused on the development of highly integrated arrayed waveguide gratings (AWGs) for optical spectrometry applications. We explored the integration of AWGs on various photonic waveguide platforms for different operational wavelength ranges. In addition, we investigated the integration of an advanced material such as graphene with the device. These factors are crucial for AWG-based spectrometers, as they can significantly influence the efficiency, compactness, and cost-effectiveness of the device.
What are the key findings or observations of your doctoral research?
An arrayed waveguide grating (AWG) was designed on a silicon photonics platform, enabling a more compact device footprint. Operating at an unconventional wavelength of 1800 nm, the AWG allows access to a broader range of molecular signatures, which is valuable for environmental monitoring applications. However, detection at this wavelength requires more expensive detectors compared to those used at conventional wavelengths. To overcome this limitation, we integrated graphene at the output waveguide, utilizing its saturable absorption properties. By introducing an additional wavelength of 1480 nm to saturate the graphene absorption, the device becomes compatible with conventional detectors. This approach enables a cost-effective spectrometer design with an extended detection range.
How can the results of your doctoral research be utilised in practice?
The AWG-based spectrometer can be used for environmental monitoring applications, offering a broader range of detections while maintaining a low cost.
What are the key research methods and materials used in your doctoral research?
We aimed to design an arrayed waveguide grating (AWG) capable of operating at an unconventional wavelength of 1800 nm to access a broader range of molecular signatures. First, we selected the silicon-on-insulator (SOI) platform, which offers a cost-effective fabrication process, is well-suited for operation at 1800 nm, and supports compact device designs. Our next objective was to ensure compatibility with low-cost detectors. To achieve this, we integrated graphene into the device, utilizing its saturable absorption property to enable operation with conventional detection systems.
The doctoral dissertation of Janvit Tippinit, MEng, entitled Highly integrated arrayed waveguide gratings for optical spectrometry: design and simulation will be examined at the Faculty of Science, Forestry and Technology, Joensuu Campus. The opponent will be Assistant Professor Paul Verrinder, Aalto University, and the custos will be Professor Matthieu Roussey, 91天美. Language of the public defence is English.
For more information, please contact:
Janvit Tippinit, janvit.tippinit@uef.fi
- Public examination
- (PDF)
