Overview Light is an electromagnetic wave that arises from the mutual interaction of time-varying electric and magnetic fields. The properties of such wave depend on the type and structure of the medium through which this wave passes. Metaphotonics represents the study of new optical behaviors beyond conventional optical properties by developing a new space, constructed with various artificial nanostructures.
"Meta," from Greek, means "beyond" and in the context of metaphotonics refers to artificial properties that do not exist naturally. These artificial structures can generate unusual but useful phenomena, unanticipated from naturally observed materials. Metaphotonics is capable of controlling various optical properties such as the amplitude, phase, polarization as well as the wavelength in a sub-wavelength scale. Thanks to this ability, various fields, including sensors, displays, communication, energy, and biotechnology apply the metaphotonics usefully.
Technology Trend Recent technology trends include complicated field generation; it has become possible to generate various images depending on the observation angle or the polarization of incident light. These breakthroughs allow complex hologram images for anti-counterfeiting. Ultrathin and planar form factor of the metasurfaces for imaging, i.e., metalens, have attracted significant interest, because this may replace thick and bulky lens systems in cameras and microscopes. The main hurdle is the dispersive property of the material and the resultant limited bandwidth. Recent studies have shown that this can be circumvented by making use of higher-degree-of-freedom super cell or multi-layer metasurfaces, enabling achromatic and broadband metalens. Intriguingly, contrarian moves are emerging as well; people have started to exploit such dispersive property rather than to overcome. The wavelength-dependent response of the metasurface can be utilized to implement ultra-compact spectrometers and hyperspectral imaging devices.
Meanwhile, there has been considerable and on-going effort to dynamically modulate the response of the metasurfaces. This branch is known as the active (reconfigurable) metasurface. Ultrafast and wide-angle wavefront shaping/representation will enable numerous game-changing devices such as holographic displays, beam steering for light detection and ranging (LiDAR), and free-space optical communications.
SAIT Technology SAIT is actively engaged in research on fundamentals and applications of metaphotonics. SAIT laboratories are working on developing trailblazing metalenses for innovative imaging systems with ultra-small form factors. These novel technologies will enable disruptive cameras and new designs of future mobile platforms. SAIT is also developing compact spectrometers with wide acceptance angles, which can be implemented in mobile devices and used in daily lives for food inspection and skin analysis. In addition, SAIT has been contributing to color image sensors that exploit high-efficiency color sorters. These pioneering devices may replace current color-rejection filters and boost up image quality at low luminance environment. We also conduct research on innovative tunable metasurfaces for ultra-fast beam scanners for LiDAR. With deep and extensive competencies in metasurfaces and nanomaterial technologies, we will keep ahead for the better future inspired and promised by cutting-edge technologies.