Recent progress in nanofabrication has led to tremendous technological developments for devices that rely on the interaction of light with nanostructured matter. Nanophotonics has hence experienced a large surge of interest in recent years, from basic research to applied technology. For instance, the increased importance of ultralow-energy data processing at fast speeds has been encouraging the use of light for signal transport and processing. Energy demands and interaction time scales become smaller with the physical size of the nanostructures, hence nanophotonics opens important opportunities for integrating a large number of devices that can generate, control, modulate, sense, and process light signals at ultrafast speeds and below femtojoule/bit energy levels. However, losses and diffraction pose fundamental challenges to the fundamental ability of nanophotonic structures to efficiently confine light in smaller and smaller volumes. In this framework, active nanophotonics, which combines the latest advances in nanotechnology with gain materials, has recently become a vital area of optics research, both from the physics, material science, and engineering standpoint. In this article, we review recent efforts in enabling active nanodevices for lasing and optical sources, loss compensation, and to realize new optical functionalities, like $\mathcal {P}\mathcal {T}$ -symmetry, exceptional points, and nontrivial lasing based on suitably engineered distributions of gain and loss in nanostructures.

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主动纳米光子学

纳米制造的最新进展为依赖光与纳米结构物质相互作用的设备带来了巨大的技术发展。因此，近年来，从基础研究到应用技术，纳米光子学引起了极大的兴趣。例如，高速超低能量数据处理的重要性日益增加，这一直鼓励使用光进行信号传输和处理。能量需求和相互作用时间尺度随着纳米结构的物理尺寸变小，因此纳米光子学为集成大量能够以超快速度和低于飞焦/比特的速度产生、控制、调制、感测和处理光信号的设备提供了重要的机会能量水平。然而，损耗和衍射对纳米光子结构有效地将光限制在越来越小的体积中的基本能力提出了根本性的挑战。在此框架中，将纳米技术的最新进展与增益材料相结合的有源纳米光子学最近已成为光学研究的重要领域，无论是从物理学、材料科学还是工程学的角度来看。在本文中，我们回顾了最近在使有源纳米器件用于激光和光源、损耗补偿以及实现新的光学功能方面所做的努力，例如 $\mathcal {P}\mathcal {T}$ -对称性、异常点和非平凡激光基于纳米结构中适当设计的增益和损耗分布。活性纳米光子学将纳米技术的最新进展与增益材料相结合，从物理学、材料科学和工程的角度来看，它最近已成为光学研究的重要领域。在本文中，我们回顾了最近在使有源纳米器件用于激光和光源、损耗补偿以及实现新的光学功能方面所做的努力，例如 $\mathcal {P}\mathcal {T}$ -对称性、异常点和非平凡激光基于纳米结构中适当设计的增益和损耗分布。活性纳米光子学将纳米技术的最新进展与增益材料相结合，从物理学、材料科学和工程的角度来看，它最近已成为光学研究的重要领域。在本文中，我们回顾了最近在使有源纳米器件用于激光和光源、损耗补偿以及实现新的光学功能（如 $\mathcal {P}\mathcal {T}$ -对称性、异常点和非平凡激光）方面的努力基于纳米结构中适当设计的增益和损耗分布。