(1. Department of Materials Science and Engineering, Southern University of Science and Technology, Shenzhen 518055, China) (2. Shenzhen Institute for Quantum Science and Engineering, Southern University of Science and Technology, Shenzhen 518055, China) (3. School of Information Photoelectric Science & Technology, South China Normal University, Guangzhou 510006, China)
In linear optics, the emergence and development of artificial materials such as photonic metamaterials provide more degree of freedom to control lightmatter interactions. For example, the artificial metaatoms can be used to flexibly and effectively control the amplitude, phase and polarization of light at subwavelength scales. Thus, some novel optical phenomena, such as superlens, negative refraction, and invisible cloak, have been achieved. By controlling the geometric phase of light and local electromagnetic enhancement in metamaterials, to achieve significant enhancement of lightmatter interactions, people opens a new door for realizing nonlinear micro/nano light sources and their applications. In this review, the recent research progresses of functionalities of photonic metamaterials such as optical frequency conversion, ultrafast optical switching and modulation, and nonlinear phase control are summarized. We also overview the future applications and challenges of the nonlinear photonic metamaterials.