Research in photonics has consistently focused on discovering new methods to manipulate light using optical structures. This pursuit is driven by the multitude applications of photonics that could significantly change the way we live today. For instance, the knowledge of photonics has remarkably transformed our daily lives by introducing inventions like optical fibers, cameras, lasers, sensors, computers, and mobile displays. As a vital technology, photonics holds the potential to upend various sectors ranging from healthcare, communication, digital economy, entertainment to automated industry.
“Along this line, nanophotonics offers a crucial framework for developing efficient and cost-effective photonic devices with active tunability. Over the years, active nanophotonics has been gaining significant attention as a resource for developing novel photonic devices,” says Dipa Ghindani.
Findings enable the development of actively tunable photonics devices
Active band and color filters are important for communication applications and require large spectral tunability. The metal-insulator-metal (MIM) structure is commonly used for this purpose due to its simple structure, ease of fabrication, and easily tunable spectral response.
In her research, Dipa Ghindani identified mechanisms of emission enhancement using MIM and demonstrated large active spectral tuning and emission tuning by utilizing a hydrogel based MIM cavity. In addition to tunable filters, active beam steering is also crucial in communication systems. She developed an electrical gating scheme that can operate in both transmission and reflection modes, which can be incorporated into phase gradient metasurfaces to achieve beam steering.
Imaging and sensing devices require precise fabrication for correct functionality. To compensate for fabrication errors and increase flexibility in designing plasmonic nanoantennas, Dipa demonstrated the resonance pinning effect in multi-resonance systems using epsilon near zero material, enhancing the versatility and functionality of plasmonic nanostructures.
Overall, her doctoral dissertation represents a significant contribution to the field of nanophotonics and has the potential to inspire further research and innovation in this area. Her findings are expected to facilitate the development of advanced photonic devices with active tunability, which will pave the way for new technologies and improve the quality of life for people worldwide.
Dipa Ghindani is from India and has been living in Finland the last three and half years for her doctoral studies at Tampere University.
Public defence on Friday 31 March
The doctoral dissertation of MSc (Tech) Dipa Ghindani in the field of Photonics titled Tailoring Light-matter Interaction via Advanced Nanophotonic Structures will be publicly examined in the Faculty of Engineering and Natural Sciences at Tampere University on Friday 31 March at 12 o’clock at Hervanta Campus in the Auditorium TB103 of the Tietotalo building (Korkeakoulunkatu 3, Tampere). Prof. Olivier Martin from the, École polytechnique fédérale de Lausanne (EPFL), Switzerland will act as opponent. Prof. Humeyra Caglayan from Tampere University will serve as the Custos.
The doctoral dissertation is available online.
Photo: Jonne Renvall