Guiding principle of light waves through metamaterial layers

Coherent excitation-selective spectroscopy in planar metamaterials

In a proof-of-principle experiment with metamaterials exhibiting electric dipolar and magnetic dipolar resonances, we demonstrated that the electric and magnetic resonances can be separately switches off and on by positioning the metamaterials along a standing wave, while both resonances are present in travelling-wave spectra.

Unidirectional Loop Metamaterials (ULM) as Magnetless Artificial Ferrimagnetic Materials: Principles and Applications

This paper presents an overview of Unidirectional Loop Metamaterial (ULM) structures and applications. Mimicking electron spin precession in ferrites using loops with unidirectional loads (typically transistors), the ULM exhibits all the fundamental properties of ferrite materials, and represents the only existing magnetless ferrimagnetic medium. We present here an extended explanation of ULM physics and unified description of its component and system applications.

Generation, amplification, frequency conversion and reversal of propagation of THz photons in nonlinear hyperbolic metamaterial

The metamaterial is proposed which supports a mixture of three or more normal and backward electromagnetic modes with equal co-directed phase velocities and mutually contra-directed energy fluxes. This enables extraordinary three-wave mixing, greatly enhanced optical parametric amplification and frequency-changing generation of entangled photons in the reflection direction. Proof-of-principle numerical simulation of such processes is presented based on the particular example of the wave-guided THz waves contra-propagating in the metamaterial made of carbon nanotubes.

Optical Cloaking with Non-Magnetic Metamaterials

Artificially structured metamaterials have enabled unprecedented flexibility in manipulating electromagnetic waves and producing new functionalities, including the cloak of invisibility based on coordinate transformation. Here we present the design of a non-magnetic cloak operating at optical frequencies. The principle and structure of the proposed cylindrical cloak are analyzed, and the general recipe for the implementation of such a device is provided. The cloaking performance is verified using full-wave finite-element simulations.

Optical isolation with epsilon-near-zero metamaterials

We suggest a principle for isolation of circularly polarized waves in magnetically active extreme-parameter metamaterials. Using theoretical analysis and numerical simulations, we show that metamaterials with extreme parameters, such as epsilon-near-zero materials (ENZ), when merged with magneto-optical materials, become transparent for forward circularly polarized waves of a given handedness and opaque for backward propagating waves of the same handedness. We theoretically study two possible implementations of such hybrid materials: (1) the case of metal-dielectric stacks; and (2) rectangular…

Metamaterial Broadband Angular Selectivity

We demonstrate how broadband angular selectivity can be achieved with stacks of one-dimensionally periodic photonic crystals, each consisting of alternating isotropic layers and effective anisotropic layers, where each effective anisotropic layer is constructed from a multilayered metamaterial. We show that by simply changing the structure of the metamaterials, the selective angle can be tuned to a broad range of angles; and, by increasing the number of stacks, the angular transmission window can be made as narrow as desired. As a proof of principle, we realize the idea experimentally in the m…

Creating double negative index materials using the Babinet principle with one metasurface

Metamaterials are patterned metallic structures which permit access to a novel electromagnetic response, negative index of refraction, impossible to achieve with naturally occurring materials. Using the Babinet principle, the complementary split ring resonator (SRR) is etched in a metallic plate to provide negative ε, with perpendicular direction. Here we propose a new design, etched in a metallic plate to provide negative magnetic permeability μ, with perpendicular direction. The combined electromagnetic response of this planar metamaterial, where the negative μcomes from the aperture and the…

Complete 2π Phase Control by Photonic Crystal Slabs

Photonic crystal slabs are the state of the art in studies for the light confinement, optical wave modulating and guiding, as well as nonlinear optical response. Previous studies have shown abundant real-world implementations of photonic crystals in planar optics, metamaterials, sensors, and lasers. Here, we report a novel full 2π phase control method in the reflected light beam over the interaction with a photonic crystal resonant mode, verified by the temporal coupled-mode analysis and S-parameter simulations. Enhanced by the asymmetric coupling with the output ports, the 2π phase shift can …

Linear coupling between lightwaves in metamaterials enables lossless artificial magnetism

A well-known principle in optical physics states that power can never be exchanged between two light waves propagating inside a homogeneous medium when the medium response is strictly linear. Power exchange between light waves usually occurs with the aid of nonlinearity. A typical example is nonlinear optical parametric amplification where net energy can flow from a high-frequency (high-energy) light wave (pump) to a lower-frequency signal wave, leading to amplification of the signal wave. Here, we show that this limitation of ordinary media can be overcome using suitably engineered metamateri…

Polarization-sensitive propagation in an anisotropic metamaterial with double-sheeted hyperboloid dispersion relation

The polarization-sensitive propagation in the anisotropic metamaterial (AMM) with double-sheeted hyperboloid dispersion relation is investigated from a purely wave propagation point of view. We show that TE and TM polarized waves present significantly different characteristics which depend on the polarization. The omnidirectional total reflection and oblique total transmission can occur in the interface associated with the AMM. If appropriate conditions are satisfied, one polarized wave exhibits the total refraction, while the other presents the total reflection. We find that the opposite amph…

BaMoO3/SrHfO3双曲超材料光学性质的第一性原理研究

First-principles study of the optical properties of BaMoO3/SrHfO3 hyperbolic metamaterials

本文通过第一性原理研究BaMoO3/SrHfO3双曲超材料，预测其在可见光范围内具有双曲特性且损耗显著降低，并验证了有效介质理论的准确性。

An FET-Based Unit Cell for an Active Magnetic Metamaterial

A particle that can be used to create an active magnetic metamaterial has been designed using an FET transistor loaded in its gate by a conducting ring and in its source by a parallel resonance circuit. The design procedure is discussed and the working principle is experimentally demonstrated in the RF range.

Trapping Light in Plain Sight: Embedded Photonic Eigenstates in Zero-Index Metamaterials

Confining electromagnetic energy is crucial to enhance light-matter interactions, with important implications for science and technology. Here, we discuss the opportunities offered by trapping and confining light in open structures, based on the concept of embedded eigenstates within the radiation continuum enabled by zero-index metamaterials. Building upon the physical insights offered by our analysis, we put forward a general platform that allows realizing extremely high field enhancements in open structures under external illumination. Structures supporting embedded eigenstates represent a …

Homogenization procedure for a metamaterial and local violation of the second principle of thermodynamics

Classical theory of crystals states that a medium to be considered homogeneous must satisfy the following requirements: a) the dimension of the elementary cell must be much smaller than the incident wavelength; b) the sample must contain a large number of elementary cells, i.e. it must be macroscopic with respect to wavelength. Under these conditions, macroscopic quantities can be introduced in order to describe the optical response of the medium. We analytically demonstrate that for a symmetric elementary cell those requirements can be relaxed, and it is possible to assign a permittivity and …

Purcell Enhancement of Parametric Luminescence: Bright and Broadband Nonlinear Light Emission in Metamaterials

Single-photon and correlated two-photon sources are important elements for optical information systems. Nonlinear downconversion light sources are robust and stable emitters of single photons and entangled photon pairs. However, the rate of downconverted light emission, dictated by the properties of low-symmetry nonlinear crystals, is typically very small, leading to significant constrains in device design and integration. In this paper, we show that the principles for spontaneous emission control (i.e. Purcell effect) of isolated emitters in nanoscale structures, such as metamaterials, can be…

Coherent control of optical activity and optical anisotropy of thin metamaterials

The future fibre optic communications network will rely on photons as carriers of information, which may be stored in intensity, polarization or phase of light. However, processing of such optical information usually relies on electronics. Aiming to avoid the conversion between optical and electronic signals, modulation of light with light based on optical nonlinearity has become a major research field, but real integrated all-optical systems face thermal management and energy challenges. On the other hand, it has recently been demonstrated that the interaction of two coherent light beams on a…

Review of foundational concepts and emerging directions in metamaterial research: Design, phenomena, and applications

In the past two decades, artificial structures known as metamaterials have been found to exhibit extraordinary material properties that enable the unprecedented manipulation of electromagnetic waves, elastic waves, molecules, and particles. Phenomena such as negative refraction, bandgaps, near perfect wave absorption, wave focusing, negative Poissons ratio, negative thermal conductivity, etc., all are possible with these materials. Metamaterials were originally theorized and fabricated in electrodynamics, but research into their applications has expanded into acoustics, thermodynamics, seismol…

金属矩形波导中填充单轴负磁导率介质的静磁波

Magnetostatic waves in metallic rectangular waveguides filled with uniaxial negative permeability media

本文研究金属矩形波导中填充单轴负磁导率超材料板的静磁波传播特性，给出了色散关系、模式图样、截止频率等解析与数值结果，有助于负磁导率材料的开发。

Plasmonic Metamaterial Perovskite Solar Cells: Fundamental Tradeoffs, Limitations, and Opportunities

Whether dispersal of plasmonic nanoparticles (NPs) within a perovskite active layer can increase the efficiency of solar cells is a long-standing question. It is well known that inclusion of metallic NPs in an active layer can boost the surrounding near-field intensity around them owing to the dipolar localized surface plasmon resonance (LSPR, also called antenna effect), which can increase light absorption by solar cells. However, the use of plasmonic NPs in perovskite solar cells has been barely reported, and it is not known whether inserting plasmonic NPs into a perovskite active layer prod…

Half-wave plate based on a birefringent metamaterial in the visible range

In the present paper, a half-wave plate (HWP) based on a birefringent metamaterial is numerically designed to operate in the visible range. The proposed structure consists of an array of double-pattern perpendicular rectangular aperture (RAA) engraved into opaque silver film deposited on a glass substrate. One of the apertures is glass filled. The operating principle of this plate is based on the excitation and the propagation of one guided mode inside each aperture but with different effective index. At the output side, a phase difference is obtained whose value mainly depends on the metal th…

超材料诱导电子-声学等离子体波产生的连续谱中的非传统束缚态

Unconventional bound states in the continuum from metamaterial induced electron-acoustic plasma waves

本文提出基于双网超材料基带消失均匀化电磁场的新机制，实现无其他共振干扰且参数鲁棒的连续谱束缚态，并预测了体约束电子声学波模式和拓扑表面束缚态两种新类型。

Fundamental mechanism underlying subwavelength optics of metamaterials: Charge oscillation-induced light emission and interference

Interactions between light and conducting nanostructures can result in a variety of novel and fascinating phenomena. These properties may have wide applications, but their underlying mechanisms have not been completely understood. From calculations of surface charge density waves on conducting gratings and by comparing them with classical surface plasmons, we revealed a general yet concrete picture about coupling of light to free electron oscillation on structured conducting surfaces that can lead to oscillating subwavelength charge patterns (i.e., spoof surface plasmons but without the disper…

手性纳米棒基超材料纳米等离子体学中的 Feynman 方法

Feynman's method in chiral nanorod-based metamaterial nanoplasmonics

本文提出不依赖宏观电动力学的 Feynman 式散射理论，证明并推广振荡电荷平面场公式，用以分析纳米棒及旋光超材料平板在窄激光束中的干涉效应。