This PDF contains a list of the reviewers for the Journal of Nanophotonics in 2016

A dual-band multilayer shared aperture antenna (SAA) is presented, which can recognize anomalous two-dimensional beam steering simultaneously at two distinct operating wavelengths lie in near-infrared (NIR) (λ1=1055  nm) and visible (λ2=700  nm) spectra. The supercell consists of one large cross-shaped resonator antenna (top layer) and a 2×2 square-shaped patches (bottom layer). This compact bifunctional dual-band reflectarray SAA can steer the main beam toward relatively large angles (≈40  deg) in both θ- and ϕ-planes at dual-frequency bands. The state-of-the-art techniques in antenna design are exploited to attain the minimized aperture size and negligible coupling among NIR and visible arrays. The overall height of the antenna is 275 nm (≈0.25λ1). The presented structure is customizable in form and can easily be scaled to other frequency ratios.

We theoretically demonstrate absorption enhancement in organic solar cells (OSC) due to the incorporation of titanium nitride and zirconium nitride plasmonic nanostructures. Localizing light using plasmonic nanostructures has the potential to overcome the absorption limitations of OSC and improve their power conversion efficiency. Thus, using C-MOS compatible, cheap, and abundant materials, such as refractory plasmonics, for light trapping could facilitate their commercialization. This work shows that transition metal nitrides have comparable performance to Ag when placed as the nanopatterned back electrode. In addition, the effect of adding TiN nanoparticles and nanowires inside the active layer has been analyzed.

Plasmonic nanoparticles embedded in polymer films enhance optoelectronic properties of photovoltaics, sensors, and interconnects. This work examined optical extinction of polymer films containing randomly dispersed gold nanoparticles (AuNP) with negligible Rayleigh scattering cross-sections at particle separations and film thicknesses less than (sub-) to greater than (super-) the localized surface plasmon resonant (LSPR) wavelength, λLSPR. Optical extinction followed opposite trends in sub- and superwavelength films on a per nanoparticle basis. In ∼70-nm-thick polyvinylpyrrolidone films containing 16 nm AuNP, measured resonant extinction per particle decreased as particle separation decreased from ∼130 to 76 nm, consistent with trends from Maxwell Garnett effective medium theory and coupled dipole approximation. In ∼1-mm-thick polydimethylsiloxane films containing 16-nm AuNP, resonant extinction per particle plateaued at particle separations ≥λLSPR, then increased as particle separation radius decreased from ∼514 to 408 nm. Contributions from isolated particles, interparticle interactions and heterogeneities in sub- and super-λLSPR films containing AuNP at sub-λLSPR separations were examined. Characterizing optoplasmonics of thin polymer films embedded with plasmonic NP supports rational development of optoelectronic, biomedical, and catalytic activity using these nanocomposites.

X-ray third-order nonlinear Bragg diffraction basic formulas both for monochromatic waves and for x-ray pulses are presented. The main effects are discussed. The results of rocking curves dependences on the intensity of the incident wave are presented and analyzed. The nonlinear diffraction of x-rays becomes significant due to presence of intense x-ray synchrotron sources and XFELs.

We study the nonlinear optical response of Landau-quantized graphene to an intense electromagnetic wave. In particular, we consider the high harmonic generation process. It is shown that one can achieve efficient generation of high harmonics with strong radiation fields—when the work of the wave electric field on the magnetic length is larger than the pump photon energy. In these conditions, the high harmonics generation process enhances for a wide range of the pump wave frequencies and intensities even for significant broadening of Landau levels because of impurities in the graphene.

A Yagi-Uda-like optical nanoantenna consisting of metallo-dielectric core–shell nanoparticles has been proposed, and its major characteristics have been investigated theoretically and numerically. Compared with all-dielectric nanoantennas and plasmonic nanoantennas, the proposed nanoantenna may exhibit better directivity and Purcell factor. In addition, the antenna shows high radiation efficiency over 65% for broadband operation as well. This core–shell nanoantenna, allowing a more compact design, may find potential applications in nanoscale lasers, photovoltaic, and energy-harvesting devices.

We propose devices based on doped silicon. Doped silicon is designed to act as a plasmonic medium in the midinfrared (MIR) range. The surface plasmon frequency of the doped silicon can be tuned within the MIR range, which gives rise to useful properties in the material’s dispersion. We propose various plasmonic configurations that can be utilized for silicon on-chip applications in MIR. These devices have superior performance over conventional silicon devices and provide unique functionalities such as 90-sharp degree bends, T- and X-junction splitters, and stubs. These devices are CMOS-compatible and can be easily integrated with other electronic devices. In addition, the potential for biological and environmental sensing using doped silicon nanowires is demonstrated.

The influence of Fano resonances on the nonlinear response of hybrid plasmonic nanostructures, i.e., nanoantennas loaded with a nonlinear optical material, is theoretically investigated using the combination of a surface integral equation method and an analytical model. The results demonstrate that a suitable design of the field enhancement enables the observation of optical bistability for incident conditions that would be impossible for a bare nanoantenna. This study provides new insights into the possibilities offered by Fano resonances to control the nonlinear response of hybrid plasmonic systems.

This paper presents the design, fabrication, and characterization of a D-shaped fiber coated with polyvinyl alcohol (PVA) embedding an Au grating-based relative humidity (RH) sensor. The Au grating is fabricated on a D-shaped fiber to match the wave-vector and excite the surface plasmon, and the PVA is embedded in the Au grating as a sensitive cladding film. The refractive index of PVA changes with the ambient humidity. Measurements in a controlled environment show that the RH sensor can achieve a sensitivity of 5.4 nm per relative humidity unit in the RH range from 0% to 70% RH. Moreover, the surface plasmon resonance can be realized and used for RH sensing at the C band of optical fiber communication instead of the visible light band due to the metallic grating microstructure on the D-shaped fiber.

The extraordinary progresses in the design and realization of structures in inorganic or organic thin films, whether or not including nanoparticles, make it possible to develop devices with very specific properties. Mastering the links between the macroscopic optical properties and the optogeometrical parameters of these heterogeneous layers is thus a crucial issue. We propose to present the tools used to characterize and to model thin film layers, from an optical point of view, highlighting the interest of coupling both experimental and simulation studies for improving our knowledge on the optical response of the structure. Different examples of studies are presented on copper indium gallium selenide, perovskite, P3HT:ZnO, PC70BM, organic layer containing metallic nanoparticles, and colored solar cells.

The tunable compression possibility of femtosecond light pulses using a one-dimensional photonic crystal containing a nonlinear defect layer has been numerically simulated. The nonlinear material utilized as the defect layer in the middle of the structure is assumed to contain Kerr nonlinearity and high nonlinear response with respect to the applied pump field. The compression performance of this structure in transmission mode for different pump intensities has been investigated. The simulation result shows that increasing the pumping power applied to the defect layer causes the compression factor of the structure to increase correspondingly. Moreover, the role of initial chirp rate of the incident pulse on the compression strength of the transmitted pulse has been considered.

A relatively easier and more accurate method for the determination of average size of metal nanoparticles/aggregates in silicate glasses based on ultraviolet visible (UV–Vis) spectra fitted with the Mie and Mie–Gans models was reported. Gold ions were diffused into sodalime silicate and borosilicate glasses by field-assisted solid-state ion-exchange technique using the same experimental parameters for both glasses. Transmission electron microscopy was performed to directly investigate the morphology and distribution of the dopant nanoparticles. UV–Vis spectra of the doped glasses showed broad surface plasmon resonance peaks in their fingerprint regions, i.e., at 525 and 500 nm for sodalime silicate and borosilicate glass matrices, respectively. These spectra were fitted with the Mie model for spherical nanoparticles and the Mie–Gans model for spheroidal nanoparticles. Although both the models were developed for colloidal nanoparticles, the size of the nanoparticles/aggregates calculated was accurate to within ∼10% in both the glass matrices in comparison to the size measured directly from the transmission electron microscope images.

The effect of aluminum mole fraction and incident light intensity on linear, nonlinear, and total optical absorption coefficients in GaN/AlxGa1−xN core-defected shell nanowire is theoretically investigated. The presented nanostructure is a cylindrical quantum wire including a defected shell around the cylinder core. Based on the density matrix approach and the effective mass approximation, the intersubband optical absorption coefficients are numerically calculated. The results show that the magnitude and peaks positions of optical absorption coefficients can be adjustable by varying aluminum mole fraction. The resonance peak positions of optical absorption coefficients are blueshifted by increasing of the shell region potential due to increasing of the energy difference between two energy levels.

The efficiency of an electro-optic (EO) directional coupler (DC) and a Mach–Zehnder (MZ) switch is discussed. The specific designs employ a passive waveguide core and an EO cladding. The performance of a DC switch was evaluated by numerical methods, namely coupled mode theory (CMT), eigenmode expansion (EME) method, and beam envelope method. Using the CMT and EME methods, it is shown that in the DC with a passive waveguide core and EO cladding at certain waveguide parameters the switching effect does not take place. The effect is demonstrated for the first time and suggests that careful optimization of the DC switch should be done before experimental realization of the device. The efficiency of an optimized DC switch is shown to be of an order lower than that of an MZ switch.

Different electro-optical modulator designs based on electromagnetically induced transparency are proposed. A conductor–gap–silicon input waveguide is coupled to microrings-on-disks on each side. A low voltage modulating signal is applied to the modulator in a push-pull configuration, which changes the refractive index of the embedded layer of the electro-optical polymer. The proposed microrings-on-disks and cascaded microring modulators with submicron radii can efficiently modulate the light wave with moderate propagation losses. The microring-on-disk modulator achieved ultrasmall capacitance, 1.06 fF, and low power consumption, 2.12  fJ/bit. Both modulators have low insertion losses and high extinction ratios.

Multiresonant nanoplasmonic films have numerous applications in areas such as nonlinear optics and sensing and as spectral tags. Although techniques such as focused ion beam milling and electron beam lithography can produce high-quality multiresonant films, these techniques are expensive, serial processes that are difficult to scale at the manufacturing level. Here, we present the fabrication of multiresonant nanoplasmonic films using a layered stacking technique. Periodically spaced gold nanocup substrates were fabricated using self-assembled polystyrene nanospheres followed by oxygen plasma etching and metal deposition via magnetron sputter coating. By adjusting etch parameters and initial nanosphere size, it was possible to achieve an optical response ranging from the visible to the near-infrared. Singly resonant, flexible films were first made by performing peel-off using an adhesive-coated polyolefin film. Through stacking layers of the nanofilm, we demonstrate fabrication of multiresonant films at a fraction of the cost and effort compared with top-down lithographic techniques.

A resonance model, describing an LC circuit interaction with a bipole, is established for the determination of the effective parameters of metamaterials. The dynamic descriptions of both an LC circuit and a bipole are harmonic oscillators. Their interplay will induce a frequency shift, meaning that the most efficient receiving frequency (resonance frequency) of an LC circuit (or split ring) resonator is not the LC intrinsic frequency ( Ω LC = 1 / LC ) or the atomic vibration frequency. The relationship between the susceptibilities ( χ ( 2 ) , χ ( 3 ) ) and the frequencies, including the atomic vibration frequency ( Ω 0 ), the LC intrinsic frequency ( Ω LC ), and the practical emission field frequency ( Ω ), is obtained. Compared with the other second-order harmonics, the extra DC current is much stronger, regardless of whether the system reaches resonance or not. The third-order harmonics are more likely to approach the resonance states compared with the second-order effect. Once the combined frequency is located at the resonance frequency, it is most likely to create a negative χ ( 3 ) , and with the increase of the LC intrinsic frequency, a negative χ

This theoretical work explores how various geometries of Au plasmonic nanoslit array structures improve the total optical enhancement in GaAs photodetectors. Computational models studied these characteristics. Varying the electrode spacing, width, and thickness drastically affected the enhancement in the GaAs. Peaks in enhancement decayed as Au widths and thicknesses increased. These peaks are resonant with the incident near-infrared wavelength. The enhancement values were found to increase with decreasing electrode spacing. Additionally, a calculation was conducted for a model containing Ti between the Au and the GaAs to simulate the necessary adhesion layer. It was found that optical enhancement in the GaAs decreases for increasing Ti layer thickness. Optimal dimensions for the Au electrode include a width of 240 nm, thickness of 60 nm, electrode spacing of 5 nm, and a minimum Ti thickness. Optimal design has been shown to improve enhancement to values that are up to 25 times larger than for nonoptimized geometries and up to 300 times over structures with large electrode spacing. It was also found that the width of the metal in the array plays a more significant role in affecting the field enhancement than does the period of the array.

A polarization-independent metamaterial near-perfect absorber is numerically studied in the infrared range in a two-perpendicular-nanorod design. It is shown that the absorptance and the peak wavelength associated with magnetic resonance are sensitive to the nanorod length, the thickness, and the refractive index of the spacer, while only being slightly affected by the period and the distance between neighboring nanorods. This design shows two absorption peaks with absorptance values of 89% and 83% at the wavelengths of 1.24 and 1.46  μm, respectively. Furthermore, the absorptance and the peak wavelength associated with magnetic resonance show negligible dependence on the polarization angle. These properties are advantageous for applications, including thermal sensing and selective emitters in thermophotovoltaics.

This PDF file contains the errata for “JNP Vol. 11 Issue 01 Paper JNP-2017-0110-ERR” for JNP Vol. 11 Issue 01

This PDF file contains the errata for “JNP Vol. 11 Issue 01 Paper JNP-2017-0126-ERR” for JNP Vol. 11 Issue 01