A study resulting from the collaboration between the Department of Energy and the Department of Physics of Politecnico di Milano and supported by an interdisciplinary PhD research by Silvia Rotta Loria has been published in the journal Advanced Optical Materials as a cover article.
The study explains the origin of the ultrafast optical response of titanium nitride (TiN). This material, already knownfor its refractory properties, is also attracting increasing interest because of its fast response to photo-excitation and the possibility of controlling its optical and electronic properties during synthesis.
TiN films have already been used for thermo-photovoltaic devices, for artificial photosynthesis or for micro super-capacitors on chips. Moreover, TiN is compatible with technologies used in digital electronics. Overall, it is therefore a material with a great potential for developing ultrafast photonic devices.
This collaboration has made it possible to thoroughly study this material of great technological interest and to clarify the origin of its peculiar response to light excitation, which can be engineered through the manufacturing procedure,
Prof. Margherita Zavelani Rossi, Department of Energy, co-author of the paper
The study was carried out thanks to the synergy between two Departments of Politecnico: TiN films were made in the NanoLab (Micro and Nanostructured Materials Lab) of the Department of Energy, were then characterised in the ultrafast spectroscopy laboratories of the Department of Physics, and the experimental data were interpreted using a model developed in the Department of Physics.
Thanks to the accurate numerical model developed, it is now possible to determine how the response of a titan nitride thin film can be controlled through light; this knowledge is crucial for developing new miniaturised opto-electronic and photonic devices,
Prof. Giuseppe Della Valle, Department of Physics, co-author of the paper
The experiment mentioned in the paper is one of the outcomes of the METAFAST project funded by the European Union’s H2020-FET-OPEN programme, coordinated by Prof. Giuseppe Della Valle. The project aims to develop a new class of ultrafast optical devices based on special nanostructured surfaces (nonlinear metasurfaces).
