Metasurfaces Towards Tunable And Reconfigurable Meta Devices

Metasurfaces: Towards Tunable and Reconfigurable Meta-devices

Metamaterials and metasurfaces are developing exciting new frontier researches on reconfigurable materials with promising applications on tunable and active devices. The combination of metamaterials and microsystems not only uncap the controllability limits of optical metamaterials, but also pave the way for vast applications. This book focuses on structural reconfiguration of metasurfaces and metamaterials using microsystems, which have previously been developed for tiny machines and droplets formations. It covers multi-disciplinary researches on reconfigurable metamaterials and metasurfaces revealing their potential applications on densely integrated devices with working frequencies ranging from GHz to infrared region. Topics like MEMS metamaterials, frequency selective surface, photonic reconfigurable metasurfaces, and microfluidic metamaterials are just a few examples, which present lively research communities within the scope of this book. This book is intended for undergraduate and graduate students who are interested in fundamental science and technology of micro-optics and artificial materials, researchers in the field of reconfigurable and tunable metamaterials, and engineers working on tunable lens, Lidar, beam steering devices, or other applications.

Tunable and Reconfigurable Optical Metamaterials

Multifunctional Metasurfaces

In recent years, we have witnessed a rapid expansion of using super-thin metasurfaces to manipulate light or electromagnetic wave in a subwavelength scale. However, most designs are confined to a passive scheme and monofunctional operation, which hinders considerably the promising applications of the metasurfaces. Specifically, the tunable and multifunctional metasurfaces enable to facilitate switchable functionalities and multiple functionalities which are extremely essential and useful for integrated optics and microwaves, well alleviating aforementioned issues. In this book, we introduce our efforts in exploring the physics principles, design approaches, and numerical and experimental demonstrations on the fascinating functionalities realized. We start by introducing in Chapter 2 the "merging" scheme in constructing multi-functional metadevices, paying particular attention to its shortcomings issues. Having understood the merits and disadvantages of the "merging" scheme, we then introduce in Chapter 3 another approach to realize bifunctional metadevices under linearly polarized excitations, working in both reflection and transmission geometries or even in the full space. As a step further, we summarizes our efforts in Chapter 4 on making multifunctional devices under circularly polarized excitations, again including designing principles and devices fabrications/characterizations. Starting from Chapter 5, we turn to introduce our efforts on using the "active" scheme to construct multifunctional metadevices under linearly polarized wave operation. Chapter 6 further concentrates on how to employ the tunable strategy to achieve helicity/frequency controls of the circularly polarized waves in reflection geometry. We finally conclude this book in Chapter 7 by presenting our perspectives on future directions of metasurfaces and metadevices.