Reconstruction of light profiles with amplitude and phase information, called holography, is an attractive optical technology with various significant applications such as three-dimensional imaging and optical data storage. Subwavelength spatial control of both amplitude and phase of light is an essential requirement for an ideal hologram. However, traditional holographic devices suffer from their restricted capabilities of incomplete modulation in both amplitude and phase of visible light; this results in sacrifice of optical information and undesirable occurrences of critical noises in holographic images. Herein, we have proposed a novel metasurface that is capable of completely controlling both the amplitude and phase profiles of visible light independently with subwavelength spatial resolution. The full, continuous, and broadband control of both amplitude and phase was achieved using X-shaped meta-atoms based on the expanded concept of the Pancharatnam-Berry phase. The first experimental demonstrations of the complete complex-amplitude holograms with subwavelength definition at visible wavelengths were achieved, and excellent performances with a remarkable signal-to-noise ratio as compared to those of traditional phase-only holograms were obtained. Extraordinary control capability with versatile advantages of our metasurface paves a way to an ideal holography, which is expected to be a significant advancement in the field of optical holography and metasurfaces.

A novel method to launch finite power Airy beams based on a metasurface is presented. By tailoring the amplitude and phase of the transmitted fields from a metallic C‐aperture array, launching Airy beams is achieved in free space. The amplitude and phase of the Airy beam profile can be mapped and tailored by tuning only the tilt angles of the aperture. This structure has multifrequency characteristics, which facilitates Airy beam steering because the trajectory of Airy beams is dependent on the wavelength. In addition, the design method can generate Airy beams which have a very compact main lobe (≈2 µm). Computational and experimental results show that proposed metasurface can overcome some limitations of the traditional methods to generate Airy beams. The results can be used for potential applications in integrated optics, beam shaping, biosensing, and next‐generation holography.

Polarization is one of the fundamental properties of light, which is inherited from the vectorial nature of electromagnetic waves. Measuring states of polarizations (SOPs) is widely used for remote sensing applications. A number of ultracompact polarimeters that analyze SOPs at a single detection without splitting of incident beams have been demonstrated recently. However, the development of a broadband polarimeter remains challenging due to the resonant feature of their building blocks. Here, an ultracompact polarimeter that retrieves the SOP of incident light with broad operation bandwidth at near-infrared wavelengths is proposed. Surface plasmon polaritons (SPPs) excited by X-shaped aperture arrays are utilized as intensity probes. Full-Stokes parameters are retrieved by detecting the SPP intensities. The proposed polarimeter is demonstrated experimentally and can measure SOPs at wavelengths from 750 nm to 1050 nm. This work can help to develop more compact polarization-sensitive optical systems, such as polarimetry, ellipsometry, and optical routers.

Since the surface plasmon polariton (SPP) has received a great deal of attention because of its capability of guiding light within the subwavelength scale, finding methods for arbitrary SPP field generation has been a significant issue in the area of integrated optics. To achieve such a goal, it will be necessary to generate a plasmonic complex field. In this paper, we propose a novel method for generating a plasmonic complex field propagating with arbitrary curvatures by using double-lined distributed nanoslits. As a unit cell, two facing nanoslits are used for tuning both the amplitude and the phase of excited SPPs as a function of their tilted angles. For verification of the proposed design rule, the authors experimentally demonstrate some plasmonic caustic curves and Airy plasmons.

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