Wavefront ≈ Wavefront
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Wireless Communications Through Reconfigurable Intelligent Surfaces Open
The future of mobile communications looks exciting with the potential new use cases and challenging requirements of future 6th generation (6G) and beyond wireless networks. Since the beginning of the modern era of wireless communications, …
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A review of metasurfaces: physics and applications Open
Metamaterials are composed of periodic subwavelength metal/dielectric structures that resonantly couple to the electric and/or magnetic components of the incident electromagnetic fields, exhibiting properties that are not found in nature. …
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High‐Efficiency Dielectric Huygens’ Surfaces Open
Optical metasurfaces have developed as a breakthrough concept for advanced wave‐front engineering enabled by subwavelength resonant nanostructures. However, reflection and/or absorption losses as well as low polarization‐conversion efficie…
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Recent advances in planar optics: from plasmonic to dielectric metasurfaces Open
This article reviews recent progress leading to the realization of planar optical components made of a single layer of phase shifting nanostructures. After introducing the principles of planar optics and discussing earlier works on subwave…
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Phase Retrieval with Application to Optical Imaging: A contemporary overview Open
This review article provides a contemporary overview of phase retrieval in optical imaging, linking the relevant optical physics to the signal processing methods and algorithms. Our goal is to describe the current state of the art in this …
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Polarization-Insensitive Metalenses at Visible Wavelengths Open
In this Letter, we demonstrate highly efficient, polarization-insensitive planar lenses (metalenses) at red, green, and blue wavelengths (λ = 660, 532, and 405 nm). Metalenses with numerical apertures (NA) of 0.85 and 0.6 and corresponding…
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Orbital angular momentum microlaser Open
Microlasers with a twist Structured light, in the form of helical wavefronts, provides an additional degree of freedom to encode information for optical communications. Creating light beams with the desired amount of optical angular moment…
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A Review on Metasurface: From Principle to Smart Metadevices Open
Metamaterials are composed of periodic subwavelength metallic/dielectric structures that resonantly couple to the electric and magnetic fields of the incident electromagnetic waves, exhibiting unprecedented properties which are most typica…
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Nonlinear metasurfaces: a paradigm shift in nonlinear optics Open
Frequency conversion processes, such as second- and third-harmonic generation, are commonly realized in nonlinear optics, offering opportunities for applications in photonics, chemistry, material science and biosensing. Given the inherentl…
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First light for GRAVITY: Phase referencing optical interferometry for the Very Large Telescope Interferometer Open
GRAVITY is a new instrument to coherently combine the light of the European Southern Observatory Very Large Telescope Interferometer to form a telescope with an equivalent 130 m diameter angular resolution and a collecting area of 200 m 2 …
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Gradient metasurfaces: a review of fundamentals and applications Open
In the wake of intense research on metamaterials the two-dimensional analogue, known as metasurfaces, has attracted progressively increasing attention in recent years due to the ease of fabrication and smaller insertion losses, while enabl…
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Metagratings: Beyond the Limits of Graded Metasurfaces for Wave Front Control Open
Graded metasurfaces exploit the local momentum imparted by an impedance gradient to transform the impinging wavefront. This approach suffers from fundamental limits on the overall conversion efficiency and it is challenged by fabrication l…
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From the generalized reflection law to the realization of perfect anomalous reflectors Open
Nonlocal metasurface for perfect anomalous reflection demonstrates a new possibility for controlling electromagnetic energy flow.
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Dielectric Metasurfaces for Complete and Independent Control of Optical\n Amplitude and Phase Open
Metasurfaces are optically thin metamaterials that promise complete control\nof the wavefront of light but are primarily used to control only the phase of\nlight. Here, we present an approach, simple in concept and in practice, that\nuses …
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Achromatic Metasurface Lens at Telecommunication Wavelengths Open
Nanoscale optical resonators enable a new class of flat optical components called metasurfaces. This approach has been used to demonstrate functionalities such as focusing free of monochromatic aberrations (i.e., spherical and coma), anoma…
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Wave-front Transformation with Gradient Metasurfaces Open
Relying on abrupt phase discontinuities, metasurfaces characterized by a transversely inhomogeneous surface impedance profile have been recently explored as an ultrathin platform to generate arbitrary wave fronts over subwavelength thickne…
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The Subaru Coronagraphic Extreme Adaptive Optics System: Enabling High-Contrast Imaging on Solar-System Scales Open
The Subaru Coronagraphic Extreme Adaptive Optics (SCExAO) instrument is a multipurpose high-contrast imaging platform designed for the discovery and detailed characterization of exoplanetary systems and serves as a testbed for high-contras…
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Feedback-based wavefront shaping Open
Light scattering was thought to be the fundamental limitation for the depth at which optical imaging methods can retain their resolution and sensitivity. However, it was shown that light can be focused inside even the most strongly scatter…
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Fabrication of ideal geometric-phase holograms with arbitrary wavefronts Open
Throughout optics and photonics, phase is normally controlled via an optical path difference. Although much less common, an alternative means for phase control exists: a geometric phase (GP) shift occurring when a light wave is transformed…
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Polarization-Independent Silicon Metadevices for Efficient Optical Wavefront Control Open
We experimentally demonstrate a functional silicon metadevice at telecom wavelengths that can efficiently control the wavefront of optical beams by imprinting a spatially varying transmittance phase independent of the polarization of the i…
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Metascreen-Based Acoustic Passive Phased Array Open
Conventional phased arrays require a large number of sources in forming a complex wave front, resulting in complexity and a high cost to operate the individual sources. We present a passive phased array using an acoustic metascreen that tr…
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Convert Acoustic Resonances to Orbital Angular Momentum Open
We use acoustic resonances in a planar layer of half-wavelength thickness to twist wave vectors of an in-coming plane wave into a spiral phase dislocation of an outgoing vortex beam with orbital angular momentum (OAM). The mechanism is num…
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Adaptive metalenses with simultaneous electrical control of focal length, astigmatism, and shift Open
Artificial muscle corrects metalens aberrations on the fly.
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Adaptive dynamic range shift (ADRIFT) quantitative phase imaging Open
Quantitative phase imaging (QPI) with its high-contrast images of optical phase delay (OPD) maps is often used for label-free single-cell analysis. Contrary to other imaging methods, sensitivity improvement has not been intensively explore…
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Implementation of dispersion-free slow acoustic wave propagation and phase engineering with helical-structured metamaterials Open
The ability to slow down wave propagation in materials has attracted significant research interest. A successful solution will give rise to manageable enhanced wave–matter interaction, freewheeling phase engineering and spatial compression…
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Athermally photoreduced graphene oxides for three-dimensional holographic images Open
The emerging graphene-based material, an atomic layer of aromatic carbon atoms with exceptional electronic and optical properties, has offered unprecedented prospects for developing flat two-dimensional displaying systems. Here, we show th…
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Three-dimensional chiral microstructures fabricated by structured optical vortices in isotropic material Open
Optical vortices, a type of structured beam with helical phase wavefronts and 'doughnut'-shaped intensity distributions, have been used to fabricate chiral structures in metals and spiral patterns in anisotropic polarization-dependent azob…
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Demonstration of a low-frequency three-dimensional terahertz bullet with extreme brightness Open
The brightness of a light source defines its applicability to nonlinear phenomena in science. Bright low-frequency terahertz (<5 THz) radiation confined to a diffraction-limited spot size is a present hurdle because of the broad bandwidth …
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A Fully Phase‐Modulated Metasurface as An Energy‐Controllable Circular Polarization Router Open
Geometric metasurfaces primarily follow the physical mechanism of Pancharatnam–Berry (PB) phases, empowering wavefront control of cross‐polarized reflective/transmissive light components. However, inherently accompanying the cross‐polarize…
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Anomalous Refraction of Acoustic Guided Waves in Solids with Geometrically Tapered Metasurfaces Open
The concept of a metasurface opens new exciting directions to engineer the refraction properties in both optical and acoustic media. Metasurfaces are typically designed by assembling arrays of subwavelength anisotropic scatterers able to m…