Mid-Infrared photonic sources and devices

中红外光谱区（mid-IR）是由大多数常见分子（甲烷、臭氧、水、二氧化碳等）的强振动跃迁组成的，近年来已成为最重要的科学和技术光谱区。毫不奇怪，中红外激光源以及相应的传输和处理设备（例如波导，传感器等）已经证明了它们在光谱学，材料加工和生物分子传感等几个应用中的重要性。许多环境（远程蒸汽痕迹探测）、安全（导弹对抗）和通信（隐蔽通信系统）应用也可以受益于覆盖3-5微米和8-13微米两个大气传输窗口的中红外源。现在，中红外光源、组件和设备的发展面临着一些需要解决的实际和基本挑战。因此，本提案的主要目的是专门解决与中红外光纤激光器和中红外集成光子元件发展有关的基本挑战。****为了实现这一目标，我们将利用光子学使得现在可以通过非线性激光物质相互作用来修改材料特性。事实上，飞秒脉冲具有在透明材料的精确区域上完美控制能量沉积速率的能力，因此可以非常精确地改变其物理和光学特性。这对各种新工艺至关重要，例如在玻璃上刻字波导或反射结构；将透明介电材料焊接在一起或与其他材料如晶体（蓝宝石、钻石、YAG、ZnSe等）或金属焊接；电介质材料的精密切割或穿孔现在，很明显，这种光致3D光子元件的飞秒铭文的全部潜力尚未被探索用于中红外光谱区域的材料和设备。这就是我们的研究活动的方向，尽管我们的发现基金的目标主要是解决这种发展的基本方面，但其结果可能会产生重大的社会经济影响，即在生物医学、电信和国防与安全领域

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.***