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We have reported exceptionally high electromagnetic interference (EMI) shielding effectiveness (SE) for flexible weaved carbon fiber fabrics (CFFs), which were spray-coated with Ag nanoparticle ink without surface modification of the CFF substrate. CFFs spray coated with Ag on a roll-to-roll (R2R) platform with a total composite thickness of 460 μm exhibited a remarkable EMI SE of 102 dB, with a density of 0.52 g cm−3. The specific EMI SE and absolute EMI SE obtained were 194 dB cm3 g−1 and 4266 dB cm2 g−1, respectively. These results suggest that the R2R spray coating of conductive metal inks such as Ag on CFFs is an economical, promising, and scalable approach for manufacturing fabrics with exceptional EMI SE.

We demonstrate free-space wavelength- and mode-division-multiplexed communications in the mid-infrared wavelength region. A total capacity of 300 Gbit/s is achieved using three wavelengths and two orbital angular momentum modes each carrying a 50-Gbit/s QPSK signal.

Metasurfaces are arrays of subwavelength meta-atoms that shape waves in a compact and planar form factor. Analysis and design of metasurfaces require methods for modeling their interactions with waves. Conventional modeling techniques assume that metasurfaces are locally periodic structures excited by plane waves, restricting their applicability to gradually varying metasurfaces that are illuminated with plane waves. Here we introduce the discrete-space impulse response concept that enables the development of accurate and general models for metasurfaces. According to the proposed model, discrete impulse responses are assigned to metasurface unit cells and are used to determine the metasurface response to any arbitrary incident waves. We verify the accuracy of the model by comparing its results with full-wave simulations. The proposed concept and modeling technique are applicable to linear metasurfaces with arbitrary meta-atoms, and the resulting system-level models can be used to accurately incorporate metasurfaces into simulation and design tools that use wave or ray optics.

The recent development of efficient dielectric metasurfaces has enabled practical optical components and systems composed of multiple cascaded metasurfaces. In this talk, I present an overview of our work on modeling, design, and implementation of cascaded metasurface components and systems. In particular, I present accurate system-level models for metasurfaces, techniques for designing efficient metasurfaces, multifunctional cascaded metasurfaces, and bilayer birefringent metasurfaces that provide the ultimate control over the wavefront and polarization of light. Furthermore, I will introduce a novel technique for engineering chromatic dispersion by cascading and briefly discuss a single-snapshot hyperspectral imager enabled by cascading multiple metasurfaces.