Wuhan National Laboratory for Optoelectronics and School of Physics, Huazhong University of Science and Technology, Wuhan 430074, China.
Department of Electrical and Computer Engineering, The University of Texas at Austin, Austin, Texas 78712, USA.
Phys Rev Lett. 2018 Mar 30;120(13):133901. doi: 10.1103/PhysRevLett.120.133901.
By using optical phase modulators in a fiber-optical circuit, we theoretically and experimentally demonstrate large control over the spectrum of an impinging signal, which may evolve analogously to discrete diffraction in spatial waveguide arrays. The modulation phase acts as a photonic gauge potential in the frequency dimension, realizing efficient control of the central frequency and bandwidth of frequency combs. We experimentally achieve a 50 GHz frequency shift and threefold bandwidth expansion of an impinging comb, as well as the frequency analogue of various refraction phenomena, including negative refraction and perfect focusing in the frequency domain, both for discrete and continuous incident spectra. Our study paves a promising way towards versatile frequency management for optical communications and signal processing using time modulation schemes.
通过在光纤电路中使用光相位调制器，我们从理论和实验上证明了对入射信号光谱的有效控制，这类似于在空间波导阵列中的离散衍射。调制相位在频率维度上充当光子 gauge 势，实现了对频率梳的中心频率和带宽的有效控制。我们在实验上实现了入射梳状光谱的 50GHz 频率移动和三倍带宽扩展，以及各种折射现象的频率模拟，包括在离散和连续入射光谱下的负折射和完美聚焦。我们的研究为使用时间调制方案进行光学通信和信号处理的灵活频率管理开辟了一条有前途的道路。
