基于带隙可调光子晶体的零相移超材料及其光学传输特性的研究

With the rapid development of information and communication industry, metamaterials with zero phase delay have become a focus of research from all walks of life. The transmission technology with zero phase delay has important applications in the fields of optical communication and signal processing. Due to the current metamaterials with zero phase delay often being achieved with the design of zero refractive index, hard fabrication and narrow frequency scope hinder its application and development. In previous research, applicants found that the phenomenon of zero phase delay can be realized in photonic crystals with the modulation of photonic band, even without zero effective refractive index, which has been verified by the simulations and experiments. In this project, we plan to achieve the phenomenon of zero phase delay in tunable photonic crystals based on the three characteristics of wavefront modulation, superposition of coherent states and Dirac point, analysis the rule of phase change and light transmission properties, and find the effective way and the general rule to realize light transmission with zero phase delay. It is necessary to clear the relations among lattice structure of photonic crystals, photonic band modulation and optical transmission characteristics, and clarify the physical mechanism and modulation method, in order to establish and perfect the theoretical framework of transmission technology with zero phase delay based on the tunable photonic crystals. The performance of this project has an important theoretical significance and practical value for the development of metamaterials with zero phase delay, which provides the theoretical basis and technical support for the development of new function materials and devices.

随着信息通讯产业的飞速发展，零相移超材料的研究已成为各界关注的热点。零相移传导技术在光通讯和信号处理领域都具有重要的应用。由于目前零相移超材料的设计往往通过零折射率实现，难于制备和频域窄都阻碍了其应用和发展。申请者在前期研究中发现通过光子晶体的能带调制，即使媒质的有效折射率非零也能够实现光的相位不变传输，并已通过仿真和实验验证了该理论。本项目拟通过带隙可调光子晶体，利用其波前调制、相干态叠加和狄拉克点的特性实现零相移传导,分析传导波的相位变化规律和光传输特性，发现实现零相移传导的有效途径和一般规律，明确光子晶体结构设计、能带调制和光传输特性三者之间的关系，阐明基于三种特性实现零相移传导的物理机制和调制方法，建立和完善基于带隙可调光子晶体的零相移传导技术的理论框架。本项目的开展对性能可调零相移超材料的发展具有重要的理论意义与实际价值，为开发新型零相移功能材料及其器件提供了理论依据和技术保障。

有效折射率为零的超材料在集成光学中具有重要的应用前景，无限波长和空间零相位变化，特别适用于芯片上光布线和信号传导。通过光子晶体中的狄拉克锥色散可以实现零指数，我们对狄拉克点及其周围的线性光色散性质开展了系统的研究，提出了利用宽频透射/反射光谱分析确认狄拉克点精确位置的方法，并利用其零折射率特性提出高精度测距方法，在不借助其他外加设备的情况下测量精度达到四分之一波长。此外，我们对狄拉克点周围线性色散锥中的电磁波传导性质也开展了深入的研究，在光子晶体中发现近零折射率情况下奇特的光波长拉伸现象，并基于该机理设计出一种半开放式的高效直角转向谐振装置设计策略，其能量传导效率大于90%。基于该原理我们提出了新型微纳精密测距方法，光开关和光传感等应用设计，使得这些更令人兴奋的应用可以集成在一个微纳平台上。光重定向在光学集成系统中起着重要的作用，从微波到可见光的应用前景十分广阔，谐振器几何尺寸和结构参数为调制工作频率提供了很大的设计灵活性。这一策略还可以推广到其他人工超材料和三维情况。本项目的开展拓展了可调零相移超材料的研究范畴，发展出具有重要理论意义与实 际应用价值的新方案，为开发新型功能材料及器件提供了理论依据和技术保障，为推动集成光子学的快速发展提供了动力。