Designing silicon-core fiber tapers for efficient mid-IR supercontinuum generation (Conference Presentation)
Designing silicon-core fiber tapers for efficient mid-IR supercontinuum generation (Conference Presentation)
复制标题
设计硅芯光纤锥度以实现高效的中红外超连续谱生成（会议演示）
DOI：
10.1117/12.2555810
复制
发表时间：
2020
期刊：
影响因子：
--
通讯作者：
Campling J
中科院分区：
文献类型：
--
作者：
Campling J
提出了一种用于2.1μm脉冲光纤激光器产生超连续谱（SC）的硅芯光纤锥形设计。该设计旨在最大限度地提高3-4μm区域的转换效率（CE），这对于环境传感非常重要，因为它包括几个关键的温室气体吸收线。需要紧凑、低功耗和高效的解决方案。氮化铝光子芯片波导在3-4μm波段的输出功率为0.3mW，输入功率为80 mW。虽然这对于某些应用来说是足够的功率，但该系统仅提供0.4%的CE。最近，氮化硅平面波导被用于通过色散波产生将能量从商业2.1μm飞秒激光器转移到3-4μm区域的目标波长。为了覆盖整个区域，估计将需要40 mW的输入来产生~ 1 mW（CE为2.5%）。与这些材料相比，硅具有更高的非线性，并且尽管有多光子吸收，但在以适度的输入功率将能量转移到不同波长时非常有效。此外，硅芯光纤可以使用已建立的后处理过程来锥形化，这可以用于控制相位匹配条件以将能量集中在所需的波长范围内。我们设计了一种硅芯光纤拉锥，它可以接收2.1μm光纤激光器的输入，并有效地传输能量，覆盖整个3-4μm范围。 我们模拟SC生成使用广义非线性薛定谔方程，包括波长相关的损失项（线性，TPA和3 PA）。从这些模拟中，我们估计，约0.8mW的平均功率可以产生覆盖整个3-4μm的区域，只有15 mW的输入功率，CE为5%。
We propose a taper design for a silicon-core fiber for the purpose of generating a supercontinuum (SC) from a 2.1μm pulsed fiber laser. The design is tailored to maximise the conversion efficiency (CE) to the 3-4μm region, which is important for environmental sensing as it includes several key greenhouse gas absorption lines. There is a need for compact, low-power and efficient solutions. Aluminium nitride photonic-chip waveguides have been shown to generate 0.3mW in the 3-4μm region with an 80mW input. Although this is sufficient power for some applications, the system only offers a 0.4% CE. More recently a silicon nitride planar waveguide was used to transfer energy from a commercial 2.1μm femtosecond laser to targeted wavelengths in the 3-4μm region through dispersive wave generation. To cover the entire region, it is estimated that an input of 40mW would be needed to generate ~1mW (CE of 2.5%). Compared to these materials silicon has a higher nonlinearity and, despite multi-photon absorption, is highly efficient at transferring energy to different wavelengths with modest input powers. Moreover, silicon-core fibers can be tapered using established post-processing procedures, which can be used to control the phase-matching conditions to concentrate energy in a required wavelength range. We have designed a silicon-core fiber taper that can take the input from a 2.1μm fiber laser and efficiently transfer the energy to cover the entire 3-4μm range. We simulated SC generation using the generalised nonlinear Schrödinger equation including wavelength-dependent loss terms (linear, TPA and 3PA). From these simulations we estimate that ~0.8mW average power can be generated covering the entire 3-4μm region, with only 15mW input power, a CE of 5%.