Institut National de la Recherche Scientifique—Énergie, Matériaux et Télécommunications, 800 de la Gauchetière Ouest, Suite 6900, Montréal, Québec H5A 1K6, Canada.
Opt Lett. 2012 Jul 1;37(13):2604-6. doi: 10.1364/OL.37.002604.
A novel, all-optical design for implementing terahertz (THz) bandwidth real-time Hilbert transformers is proposed and numerically demonstrated. An all-optical Hilbert transformer can be implemented using a uniform-period long-period grating (LPG) with a properly designed amplitude-only grating apodization profile, incorporating a single π-phase shift in the middle of the grating length. The designed LPG-based Hilbert transformers can be practically implemented using either fiber-optic or integrated-waveguide technologies. As a generalization, photonic fractional Hilbert transformers are also designed based on the same optical platform. In this general case, the resulting LPGs have multiple π-phase shifts along the grating length. Our numerical simulations confirm that all-optical Hilbert transformers capable of processing arbitrary optical signals with bandwidths well in the THz range can be implemented using feasible fiber/waveguide LPG designs.
提出并数值演示了一种新颖的全光设计，用于实现太赫兹 (THz) 带宽实时希尔伯特变换器。全光希尔伯特变换器可以使用具有适当设计的仅振幅光栅变迹轮廓的均匀周期长周期光栅 (LPG) 来实现，在光栅长度的中间引入单个 π 相移。基于所设计的 LPG 的希尔伯特变换器可以使用光纤或集成波导技术实际实现。作为推广，也可以基于相同的光学平台设计基于光子的分数希尔伯特变换器。在这种一般情况下，所得的 LPG 在光栅长度上具有多个 π 相移。我们的数值模拟证实，使用可行的光纤/波导 LPG 设计，可以实现能够处理带宽在 THz 范围内的任意光信号的全光希尔伯特变换器。
