The development of silicon-core fibers have drawn strong interest over the last decade. Indeed, silicon is a material offering interesting properties such as mid-wave infrared transparency (1-7 µm), high refractive index (3.48 @ 1.55 µm) and large third order non linearity (≈ 1.5×10−13 cm²/W). Until now, three fabrication processes have been developed to achieve glass-clad silicon-core fibers: the high-pressure microfluidic chemical deposition method , the molten core method from silicon rods  and the powder-in-tube method . This last one shows a very high potential to achieve hybrid optical fibers as it allows not only to use a wide range of materials but it is also compatible with the stack-and-draw process ; in this way, many different designs of fibers can be especially drawn. Unfortunately, fibers fabricated by this method are very short, only a few centimetres long because of the mechanical stresses accumulation at the interface between the two materials which have different thermal expansion coefficients (Si: 3×10−6 K−1; SiO2 : 5×10−7 K−1), and because of the presence of air between the grains.
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