Semiconductor activated terahertz metamaterials

Abstract

Metamaterials have been developed as a new class of artificial effective media realizing many exotic phenomena and unique properties not normally found in nature. Metamaterials enable functionality through structure design, facilitating applications by addressing the severe material issues in the terahertz frequency range. Consequently, prototype functional terahertz devices have been demonstrated, including filters, antireflection coatings, perfect absorbers, polarization converters, and arbitrary wavefront shaping devices. Further integration of functional materials into metamaterial structures have enabled actively and dynamically switchable and frequency tunable terahertz metamaterials through the application of external stimuli. The enhanced light-matter interactions in active terahertz metamaterials may result in unprecedented control and manipulation of terahertz radiation, forming the foundation of many terahertz applications. In this paper, we review the progress during the past few years in this rapidly growing research field. We particularly focus on the design principles and realization of functionalities using single-layer and few-layer terahertz planar metamaterials, and active terahertz metamaterials through the integration of semiconductors to achieve switchable and frequency-tunable response.

Keywords

terahertz / metamaterials / semiconductor / modulation

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Acknowledgement

We acknowledge partial support from the Los Alamos National Laboratory Laboratory-Directed Research and Development program. This work was performed in part at the Center for Integrated Nanotechnologies, a US Department of Energy, Office of Basic Energy Sciences user facility. Los Alamos National Laboratory, an affirmative action equal opportunity employer, is operated by Los Alamos National Security for the National Nuclear Security Administration of the US Department of Energy under contract DE-AC52-06NA25396.

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2014 Higher Education Press and Springer-Verlag Berlin Heidelberg