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The interaction between standing Sommerfeld microwaves within a system comprising two closely spaced conducting rings gives rise to pronounced resonance phenomena. The behavior of this system depends on the relative arrangement of the receiving and transmitting points. Specifically, it leads to a sharp reduction or enhancement of signal output within a narrow frequency range. Remarkably, this structure can serve dual roles: acting as both a band-stop filter and a band-pass filter, all within the same restricted frequency band. [ABSTRACT FROM AUTHOR]

We report on the design and experimental verification of angle and polarization insensitive mid-infrared filters based on dense arrays of dielectric resonators embedded into a metallic film. We experimentally show filters with 60% peak transmission for angles from 0 to 60 degrees for perpendicular polarization states. We also study the surface plasmonic mode excited due to the periodicity of the micro-resonators in the array. Simulations support the experimental results for both the primary resonance and the plasmonic mode. Integrating these filters with IR detectors offers multispectral imaging and improved search and track capability.

A spatial-frequency thin-film filter with inclusions of nanoparticles operating in the visible range of the spectrum is investigated. The effect of nanoparticles embedded in the central and lateral layers of the frustrated total internal reflection filter on the spectral characteristics, considering the frequency dispersion, is investigated. It is shown that plasmonic effects cause the splitting of the filter bandwidth into a set of narrow-band spectral lines and the angular splitting of the incident beam into a set of output beams. It is demonstrated that due to the difference in the resonance conditions for s- and p-polarization waves, the spectral lines of transparency do not coincide, which indicates the possibility of using the filter as a polarizer. [ABSTRACT FROM AUTHOR]

A spatial-frequency thin-film filter with inclusions of nanoparticles operating in the visible range of the spectrum is investigated. The effect of nanoparticles embedded in the central and lateral layers of the frustrated total internal reflection filter on the spectral characteristics, considering the frequency dispersion, is investigated. It is shown that plasmonic effects cause the splitting of the filter bandwidth into a set of narrow-band spectral lines and the angular splitting of the incident beam into a set of output beams. It is demonstrated that due to the difference in the resonance conditions for s- and p-polarization waves, the spectral lines of transparency do not coincide, which indicates the possibility of using the filter as a polarizer.

An analytical solution to the problem of wave transport of matter through composite hyper-fine barriers is constructed. It is shown that, for a composite membrane consisting of two identical ultra-thin layers, there are always distances between the layers at which the resonant passage of one of the components is realized. Resonance makes it possible to separate de Broiler waves of particles with the same properties, which differ only in masses. Broad bands of hyper-selective separation of a hydrogen isotope mixture are found at the temperature of 40 K.

We report the patterned synthesis of ZnO nanorod arrays of diameters between 50 nm and 130 nm and various spacings. This was achieved by patterning hole arrays in a polymethyl methacrylate layer with electron beam lithography, followed by chemical synthesis of ZnO nanorods in the patterned holes using the hydrothermal method. The fabrication of ZnO nanorod waveguide arrays is also demonstrated by embedding the nanorods in a silver film using the electroplating process. Optical transmission measurement through the nanorod waveguide arrays is performed and strong resonant transmission of visible light is observed. We have found the resonance shifts to a longer wavelength with increasing nanorod diameter. Furthermore, the resonance wavelength is independent of the nanowaveguide array period, indicating the observed resonant transmission is the effect of a single ZnO nanorod waveguide. These nanorod waveguides may be used in single-molecule imaging and sensing as a result of the nanoscopic profile of the light transmitted through the nanorods and the controlled locations of these nanoscale light sources. [ABSTRACT FROM AUTHOR]

Establishing a highly efficient photon-emitter interface where the intrinsic linewidth broadening is limited solely by spontaneous emission is a key step in quantum optics. It opens a pathway to coherent light–matter interaction for, e.g., the generation of highly indistinguishable photons, few-photon optical nonlinearities, and photon-emitter quantum gates. However, residual broadening mechanisms are ubiquitous and need to be combated. For solid-state emitters charge and nuclear spin noise are of importance, and the influence of photonic nanostructures on the broadening has not been clarified. We present near-lifetime-limited linewidths for quantum dots embedded in nanophotonic waveguides through a resonant transmission experiment. It is found that the scattering of single photons from the quantum dot can be obtained with an extinction of 66 ± 4%, which is limited by the coupling of the quantum dot to the nanostructure rather than the linewidth broadening. This is obtained by embedding the quantum dot in an electrically contacted nanophotonic membrane. A clear pathway to obtaining even larger single-photon extinction is laid out; i.e., the approach enables a fully deterministic and coherent photon-emitter interface in the solid state that is operated at optical frequencies. [ABSTRACT FROM AUTHOR]

This work considers the confining and scattering phenomena of electrons in a Lieb lattice subjected to the influence of a rectangular electrostatic barrier. In this setup, hopping amplitudes between nearest neighbors in orthogonal directions are considered different, and the next-nearest neighbor interaction describes spin–orbit coupling. This makes it possible to confine electrons and generate bound states, the exact number of which is exactly determined for null momentum parallel to the barrier. In such a case, it is proved that one even and one odd bound state is always generated, and the number of bound states increases for non-null and increasing values of the parallel momentum. That is, current-carrying states are generated. In the scattering regime, the energies are determined so that resonant tunneling occurs. The existence of perfect tunneling energy in the form of super-Klein tunneling is proved to exist regardless of the bang gap opening. Finally, it is shown that perfect reflection appears when solutions are coupled to the intermediate flat-band solution. • Lieb lattice with NNN hopping (Haldane-like) under external electrostatic potential. • Current-carrying localized states are determined in the well-like regime. • A modified Snell-like law is introduced for scattering waves in anisotropic lattices. • Resonant and perfect transmission energies are found in the barrier-like setup. • The existence of flat-band solutions leads to perfectly reflected waves. [ABSTRACT FROM AUTHOR]

Electromagnetic wave transmission through one dimensional multilayer plasmas, consisting of air and plasma, and having graded optical thickness is analyzed for under dense plasma ( ω > ω p ) and over-dense plasma ( ω < ω p ). Transmittivity of such a structure is found by solving wave equations and matching the electric field and its derivatives at the boundaries. It is observed that gradation in the thickness of either air or plasma or both simultaneously; leads to increase in the number of resonant frequency for under dense and over dense plasma. Respective resonant frequency is found to be shifted towards higher and lower frequency for over dense and under dense plasma for the gradation in the thickness of constituent materials. It is also found that by proper choice of gradation parameters, transmission of electromagnetic waves through such multilayer structure can be controlled and tuned to a particular frequency regime. [ABSTRACT FROM AUTHOR]

Whereas noble metal films deposited directly onto an undulated photosensitive polymer exhibit plasmon-mediated resonant transmission of free-space waves accompanied by excess losses of approximately 40 %, adequate hard baking of the photosensitive polymer, together with pre- and post-deposition of nanometer-thick ZnS or MgF dielectric interfacial layers, restores excellent propagation conditions for the long-range plasmon mode, reducing resonant transmission excess losses to 10 %, and creating the conditions for the experimental evidence of the long-sought plasmonic anomalous reflection phenomenon. [ABSTRACT FROM AUTHOR]

The quantum transport in a p-type narrow channel device with a DC-biased double finger gate is investigated using a Luttinger four-band Hamiltonian and a propagation matrix approach. The results show that when the potential energy modulation effect produced by the finger gate is large, the quantum transport shows a resonance behavior indicative of large barriers in a double-barrier system. A simple analytical method based on an ideal resonant square quantum well approximation is used to predict the energies of the resonance peaks contributed by the light and heavy holes. The results show that the first conductance peak is formed at 2 e 2 / h and is contributed by the heavy holes. A second conductance resonance peak is formed at 3 e 2 / h due to the semi-reflection of the heavy holes and resonant transmission of the light holes. Finally, a third conductance resonance peak is formed at 4 e 2 / h as a result of the concurrent resonant transmission of the light holes and heavy holes. • Quantum transport in a p-type device with a double finger gate is investigated. • Predict the energies of the resonance peaks by the light and heavy holes. • The peak at 2 e 2 / h and is contributed by the heavy holes. • The resonance peak at 3 e 2 / h is due to the semi-reflection of heavy holes and the resonant transmission of light holes. • The peak at 4 e 2 / h is a result of the concurrent resonant transmission of the light and heavy holes. [ABSTRACT FROM AUTHOR]

Whereas resonant transverse magnetic transmission across an undulated continuous metal film is achieved with the mediation of plasmon modes excited by the undulation, it is shown here that transverse electric (TE) resonant transmission through a continuous metal film can also be achieved with the mediation of the second-order TE mode of a dielectric slab waveguide having the metal film sandwiched at its middle. The demonstration is made by using the materials currently used in the domain of optical security and counterfeit deterrence: ZnS is shown to possibly be a lossless interface/adhesion layer between a polymer and a noble metal for plasmonic resonant elements. [ABSTRACT FROM AUTHOR]

The phenomenon of reflection of an electron wave in resonant propagation through periodic structures of finite length with two barriers in the periodicity cell has been investigated in relation to the parameters of the potential barriers. It has been shown that for a mirror-symmetric periodic structure this reflection is accompanied by a collapse of unit-transparency resonance peaks. A numerical calculation of the spectra of transmission coefficients and electron density of quasi-resonance states has been performed. [ABSTRACT FROM AUTHOR]

Microwave resonant transmission properties in a superconducting Fabry–Perot bilayer made of a high-temperature superconductor (YBa2Cu3O7− x) and a nearly ferroelectric superconductor ( n-SrTiO3) are theoretically investigated. The effect of high-temperature superconducting layer on the unusual resonant transmittance existing in a nearly ferroelectric superconductor is investigated. It is shown that a frequency-agile two-layer coating can be obtained with the addition of the high-temperature superconducting coating. Resonant frequencies can be shifted by varying the thickness of this coating. In addition, the ultra-narrow filtering feature makes such a bilayer resonator useful in the superconducting microwave electronics, such as a frequency sampler or spectrum analyzer in the signal processing. [ABSTRACT FROM AUTHOR]

Abstract: We study theoretically the conductance modulation through a Rashba-like quantum waveguide connected to two ferromagnet contacts based on quantum waveguide method. In this waveguide, the spin precession together with multiply reflection interference dominants the behaviors of the conductance resonance. Under the single mode approximation, the conductance exhibits periodially sharp resonant peaks with varing the length of the Rashba semiconductor, when the phase shifts of the spin-down and -up components are (m an integer), respectively, and their phase difference is mπ. For a periodic waveguide with normal metals, the modulation of the multiply reflected wave can also control the transmission. Besides, the influence of the spin polarization in the ferromagnet contacts on the conductance is examined in detail. [Copyright &y& Elsevier]

We study electron transmission through two impurities in a narrow quantum wire by solving Dyson’s equations for single electron Green functions. We have verified that, for the delta-function potential of two impurities, the Green function can be factorized into a product of the ‘free’ Green function and current transmission amplitude. Meanwhile Green function and current transmission amplitude obey Fisher-Lee’s relation. An analytical expression of the electron transmission amplitude for intrasubband and intersubband is obtained as a function of Fermi energy and the distance between two impurities. The resonant behavior of the current transmission amplitude are detail discussed. [ABSTRACT FROM AUTHOR]

We review recent theoretical calculations of charge transfer through mesoscopic devices in response to slowly-oscillating, spatially-confined, potentials. The discussion is restricted to non-interacting electrons, and emphasizes the role of quantum interference and resonant transmission in producing almost integer values (in units of the electronic charge e) of the charge transmitted per cycle, Q. The expression for the pumped charge is derived from a systematic expansion of the system scattering states in terms of the temporal derivatives of the instantaneous solutions. This yields the effect of the modulating potential on the Landauer formula for the conductance in response to a constant bias on one hand, and the corrections to the widely-used adiabatic-limit formula (in which the modulation frequency is smaller than any electronic relaxation rate) on the other hand. The expression for Q is used in connection with simple models to exemplify the intimate relationship between resonant transmissi on through the mesoscopic device and almost integral values of Q, and to analyze the charge pumped by a surface acoustic wave coupled to a quantum channel by the piezoelectric effect. [ABSTRACT FROM AUTHOR]

An analytical solution to the problem of wave transport of matter through composite hyper-fine barriers is constructed. It is shown that, for a composite membrane consisting of two identical ultra-thin layers, there are always distances between the layers at which the resonant passage of one of the components is realized. Resonance makes it possible to separate de Broiler waves of particles with the same properties, which differ only in masses. Broad bands of hyper-selective separation of a hydrogen isotope mixture are found at the temperature of 40 K. [ABSTRACT FROM AUTHOR]

Abstract: The Josephson effect in superconductor/diffusive normal metal/superconductor junctions is studied theoretically, where the p-wave pairing symmetry is assumed in superconductors. The amplitudes of the Josephson current become much larger than those in the s-wave junctions because of a cooperative effect between the midgap Andreev resonant states and the proximity effect. We show that the Josephson current is carried by the odd-frequency Cooper pairs in diffusive metals. [Copyright &y& Elsevier]

The resonant transmission of phonons propagating through a superlattice–solid interface is studied theoretically. The phonon transmission rate is calculated and the peculiar resonance peak due to the vibrational mode localized at the superlattice–solid interface is examined. Our results suggest how a superlattice can be used as an “impedance matching” device. [Copyright &y& Elsevier]

Abstract: Acoustic resonant transmission (RT) phenomenon found in Bragg couplers made of alternatively high (H) and low (L) impedance materials is theoretically investigated. The existence of the RT within the Bragg stop bands is analytically demonstrated, along with the exact peak values expressed in closed form in terms of the coupler parameters. RT takes place either when the coupler is terminated with an L-layer and has its bottom surface free, or when it is terminated with an H-layer and the bottom clamped. Numerical results are given for the transmission and reflection rates in Bragg couplers made of tungsten and SiO2 layers. [Copyright &y& Elsevier]