Metamaterials are designed by manipulating subwavelength nanostructures, providing high customization and adaptability for various applications. This PhD thesis showcases how metamaterials could be applied across diverse fields, including energy harvesting, sensing, and quantum computing.
The study began with an investigation into a lithography-free metal–insulator–metal structure, showcasing resonance properties and coupling capabilities with emitters to enhance light–matter interactions. The research progressed to explore complex multi-layered structures like polymer-based hyperbolic metamaterials, uncovering their hyperbolic dispersion relations, high spatial frequency modes, and epsilon-near-zero (ENZ) properties.
Moreover, the research investigated cylindrical metamaterials, demonstrating a novel self-rolling fabrication technique to create three-dimensional rolled-up multilayered waveguides. The study highlighted their potential as waveguide reservoirs for quantum systems, avoiding some of the constraints of traditional planar structures.
As the study delved deeper into the quantum regime, Ibrahim introduced the fabrication of a rolled-up zero-index waveguide with ENZ properties, addressing the challenges of optical interaction with distantly spaced qubits. The research demonstrated the potential of planar multilayered structures, spherical nanoparticles, and cylindrical rolled-up waveguides for classical and quantum applications.
"This thesis highlights the potential of metamaterials to shape the future of technology and science, paving the way for groundbreaking applications in various field," Issah emphasizes.
Looking ahead, the research proposes exciting future directions, including the development of thin-film metamaterials with active tuning capabilities and exploration into self-rolling mechanisms for large-scale fabrication. The investigation of quantum properties and the potential enhancement of superradiance through metamaterials open new avenues for quantum technologies. Additionally, the development of metamaterials with tailored thermal properties emerges as a crucial area for future research.
In summary, Issah's doctoral research demonstrates novel fabrication methodologies to prepare thin-film metamaterials. Fabricated metamaterials were characterized and shown to exhibit interesting possibilities to modify the occurring light–matter interactions, taking place at the nanoscale.
Ibrahim Issah is a photonics researcher focusing into fields of metamaterials and quantum technologies. His research represents a significant contribution to the scientific community and lays the foundation for future advancements in the field.
Public defence on Friday 26 January
The doctoral dissertation of M.Sc. Ibrahim Issah in the field of photonics titled Multilayer structures for enhanced light–matter interactions: Classical applications and Quantum extensions will be publicly examined at the Faculty of Engineering and Natural Sciences at Tampere University at 16.00 on Friday 26 January 2024 on remote connection only. The Opponent will be Professor Nathaniel Kinsey from Virginia Commonwealth University. The Custos will be Associate Professor Marco Ornigotti from the Faculty of Engineering and Natural Sciences.
The doctoral dissertation is available online.
The public defence can be followed via remote connection (Zoom, meeting ID: 617 2011 3877).