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If photonics and electronics are to form hybrid information processing systems, it will be necessary to manipulate and isolate light electrically, over short distances. Davoyan and Engheta propose a route to achieve this in plasmonic waveguides by exploiting the magnetic field induced by a direct current.

Unusual effects arise when a material’s permittivity or permeability approach zero, a scenario that can be readily engineered in metamaterials. This study explores the regime wherein both these quantities go to zero and the electric and magnetic fields effectively decouple while remaining temporally dynamic.

Passion for science and technology can be a powerful motivator to overcome hurdles, as Nader Engheta explains, recounting his own experience as an immigrant.

Researchers demonstrate a silicon nanowire photodetector whose gold electrical contacts render the device ‘invisible’. The wire and gold coating have opposing dipole moments that almost cancel each other out in the far-field. Although the net dipole moment is zero, a significant photocarrier population is generated in the wire.

Inspired by Boolean binary algebra, an approach to design electromagnetic metamaterials with desired permittivity by using just two elemental building blocks is demonstrated analytically and numerically.

The design of all-passive nonreciprocal metastructures is a challenging task as there are trade-offs between the nonreciprocal transmission ratio and insertion loss. Here, Mahmoud et al. propose a concept for all-passive, high-throughput metastructures that exhibit nonreciprocal properties and wave-flow isolation.

Optical analog computing has so far been mostly limited to solving a single instance of a mathematical problem at a time. Here, the authors show that the linearity of the wave equation allows to solve several problems simultaneously, and demonstrate it using an MW transmissive cavity.

Like conventional antennas, optical nanoantennas can transmit and receive signals but on much smaller length scales. Dregely et al.measure the optical power transmitted and received in the far-field by plasmonic nanoantennas and show that they can control the direction of transmission over a broad range.

Silver and silicon nitride metamaterial structures with dielectric permittivities close to zero are demonstrated at visible wavelengths. In such materials, the optical phase advance during propagation can be very small.

Here the authors proposes a mechanism to freeze and amplify electromagnetic waves via time interfaces where the permittivity of the medium is changed from positive to a Non-Foster negative value and then back to positive.

This study introduces and validates a reconfigurable metastructure that uses electromagnetic waves to perform analog complex-valued mathematical computations. This device executes both stationary and non-stationary algorithms, such as matrix inversion and optimization.

Optical-frequency antennas efficiently couple light into very small volumes. Introducing an important concept from radiofrequency antenna design, that of loading with so-called lumped circuit elements, may provide a way of tuning the frequency response of optical nanoantennas.

Lumped elements such as resistors, capacitors and inductors play a crucial role in electronic circuits. Now, inspired by metamaterials technology, the experimental realization of lumped circuit elements for optical frequencies provides a standardized platform for applications such as mixing and multiplexing of optical signals.

Using inverse design, a 3D silicon photonics platform that can be used for the mathematical operation of vector–matrix multiplication with light is demonstrated, potentially enabling large-scale wave-based analogue computing.

This paper reports an experimental observation of irrotational, inviscid, and incompressible electromagnetic power flow within an epsilon-near-zero medium, exhibiting an analogy to an ideal fluid.

This paper proposes an unconventional type of antennas that are composed by epsilon-near-zero (ENZ) media. The operating frequencies of such antennas are independent of their geometries, and are determined by material dispersion.

Being able to manipulate the temporal evolution and spatial distribution of diffusive quantities would provide exciting possibilities for applications. Here, the authors show that one can achieve large spatial asymmetric diffusion characteristics inside a metamaterial whose material parameters are space- and time-modulated.

Here, the authors demonstrate substrate-integrated photonic doping, enabling the implementation of near-zero-index media within a printed circuit board integrated design. They illustrate the potential by designing and numerically demonstrating a dielectric sensor, an acousto-microwave modulator and a flexible transmission line.

Two crystalline nanocrystals with superparamagnetic and plasmonic properties form mechanically strong hybrid nanorods with dual functionality.

Laser-based tractor beams move hollow glass particles over tens of centimetres.

Some optical forces can direct particles, but only in the direction of light propagation. Here, the authors show theoretically that when the spin of the incident circularly polarized light is converted into lateral electromagnetic momentum, it leads to a lateral optical force associated with a recoil mechanical force.

Metasurfaces can solve Fredholm integral equations of the second kind for free-space radiation at optical wavelengths. To this end, an inverse-designed metagrating is coupled to a semitransparent mirror providing feedback to perform an analogue version of the Neumann series.

Light emission of molecules can be largely impacted (enhanced or quenched) by nearby surfaces. Here, Esfandyarpour et al. engineer a high-impedance mirror that increases light emission of adjacent molecules by enhancing the coupling between the molecule and free space.

Exploiting Einstein’s theory of general relativity, the curved space associated with specially designed nanophotonic structures is shown to be able to manipulate light propagation.

The multiple photonic dopants contained in an epsilon-near-zero medium can serve as non-interacting resonators, and offer an opportunity for the independent control of electromagnetic waves at various frequencies.

Optical computing via free-space-based structured optical materials allows to access optical information without the need for preprocessing or optoelectronic conversion. In this Perspective, the authors describe opportunities and challenges in their use for optical computing, information processing, computational imaging and sensing.

Optomechanics deals with the control and applications of mechanical effects of light on matter. Here, these effects on single-material and multimaterial larger particles with size ranging from 20 nm to a 1 μm are investigated in proximity of epsilon-near-zero metamaterials exploiting different theoretical methods.

The underlying principles and unique optical applications of structures exhibiting near-zero dielectric permittivity and/or magnetic permeability are reviewed. The timely relevance to nonlinear, non-reciprocal and non-local effects is highlighted.

Light momentum inside near-zero refractive index materials is analyzed using Abraham–Minkowski discussion. It explains the absence of fundamental radiative processes, of diffraction patterns or Doppler effect inside such materials.