Mid-Infrared photonic sources and devices

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The middle infrared spectral region (mid-IR) which is comprising the strong vibrational transitions of most common molecules (methane, ozone, water, CO2, etc), has emerged recently as a spectral region of utmost scientific and technological importance. Not surprisingly though, mid-IR laser sources as well as corresponding transmitting and processing devices (e.g. waveguides, sensors, etc.) have proven how crucial they are for several applications, namely in spectroscopy, material processing and bio-molecular sensing. Numerous environmental (remote vapour trace detection), security (missile countermeasures) and communication (covert communication systems) applications could also benefit from mid-IR sources that cover the two atmospheric transmission windows of 3-5 microns and 8-13 microns. Now, the development of mid-IR sources, components and devices is facing several practical and fundamental challenges that need to be addressed. The main objective of this proposal is therefore specifically to address those fundamental challenges pertaining to the development of both mid-IR fiber lasers and mid-IR integrated photonic components.****In order to meet this objective we will take advantage of the fact that photonics makes it now possible to modify material properties through nonlinear laser matter interaction. As a matter of fact, femtosecond pulses possesses the ability to perfectly control the energy deposition rate on a precise area of a transparent material and therefore to alter their physical and optical properties very precisely. This is crucial to a variety of new processes such as the inscription of waveguiding or reflecting structures in glass; the welding transparent dielectric materials together or with other materials such as crystals (sapphire, diamond, YAG, ZnSe, etc.) or metals; the precise cutting or piercing of dielectric materials. Now, it clearly appears that the whole potential of the femtosecond inscription of such photoinduced 3D photonic components have not yet been explored for materials and devices operating in the mid-IR spectral region. This is along this line that our reseach activity will be oriented and although the objective of our discovery grant is primarily to address the fundamental aspects underlying such development, its outcome are likely to have a significant socio-economic impact, namely in biomedicine, telecommunications and defense&security.***