1 中国科学院西安光学精密机械研究所瞬态光学与光子技术国家重点实验室，陕西 西安 710119
2 中国科学院大学，北京 100049
3 南京大学固体微结构物理国家重点实验室，南京大学物理学院，江苏 南京 210093
4 南京大学人工微结构科学与技术协同创新中心，江苏 南京 210093
5 浙江大学光电科学与工程学院，浙江 杭州 310027
光学超构表面凭借其小型化集成化的优势和对光场出色的调控能力，近年来已被深入应用于光学微操控技术研究，这标志着该交叉领域进入了新的发展阶段。特别地，由于超构表面的尺寸在亚波长级别，具有被光场驱动从而产生机械运动的潜力，这一特性为新一代光驱动的人工微机器人提供了重要的理论基础和技术支撑。本文依次从光学微操控的基本原理和超表面的相位机制出发，详细回顾了基于超构表面的多种微操控器件，包括超构表面光镊、多功能微操控系统、超构机械等，并结合微纳结构的拓扑光学性质，对拓扑光操控等新奇效应进行了探讨。最后，本文展望了超构表面微操纵技术的未来发展方向和目标。
超构表面 光学微操控 光镊 光子力学
Author Affiliations
Abstract
1 State Key Laboratory of Transient Optics and Photonics, Xi’an Institute of Optics and Precision Mechanics (XIOPM), Chinese Academy of Sciences (CAS), Xi’an 710119, China
2 University of Chinese Academy of Sciences, Beijing 100049, China
3 e-mail: wfuzhang@opt.ac.cn
We investigate frequency-comb generation in normal dispersion silicon microresonators from the near-infrared to mid-infrared wavelength range in the presence of multiphoton absorption and free-carrier effects. It is found that parametric oscillation is inhibited in the telecom wavelength range resulting from strong two-photon absorption. On the contrary, beyond the wavelength of 2200 nm, where three- and four-photon absorption are less detrimental, a comb can be generated with moderate pump power, or free-carriers are swept out by a positive-intrinsic-negative structure. In the temporal domain, the generated combs correspond to flat-top pulses, and the pulse duration can be easily controlled by varying the laser detuning. The reported comb generation process shows a high conversion efficiency compared with anomalous dispersion regime, which can guide and promote comb formation in materials with normal dispersion. As the comb spectra cover the mid-infrared wavelength range, they can find applications in comb-based radiofrequency photonic filters and mid-infrared spectroscopy.
Nonlinear optics, four-wave mixing Nonlinear optics, integrated optics Parametric oscillators and amplifiers Microcavities Photonics Research
2018, 6(4): 04000238
