Two numerical studies, one based on a canonical boundary-value problem and the other based on a reflection–transmission problem, revealed that the propagation of high-phase-speed Dyakonov–Tamm (HPSDT) surface waves may be supported by the planar interface of a chiral sculptured thin film and a dissipative isotropic dielectric material. Furthermore, many distinct HPSDT surface waves may propagate in a specific direction, each with a phase speed exceeding the phase speed of plane waves that can propagate in the isotropic partnering material. Indeed, for the particular numerical example considered, the phase speed of an HPSDT surface wave could exceed the phase speed in the bulk isotropic dielectric material by a factor of as much as 10.

This PDF file contains the editorial “Special Section Guest Editorial: Nanocarbon Photonics and Optoelectronics” for JNP Vol. 11 Issue 03

The optical limiting (OL) of detonation nanodiamond (DND) suspensions in engine oil was studied at a temperature range of 20°C to 100°C. Oil suspensions were prepared on the basis of the DNDs with an average nanoparticle cluster size in hydrosols (Daver) of 50 and 110 nm. Raman spectroscopy was used to characterize the samples. The OL investigation was carried out by the z-scan technique. The fundamental (1064 nm) and second (532 nm) harmonic radiations of YAG:Nd3+ laser with passive Q-switching as an excitation source were used. The OL thresholds for both suspensions at 532 and 1064 nm were determined. It is shown that a decrease in the average nanoparticle cluster size as well as an increase of the wavelength of the incident radiation leads to the OL threshold increase. It is established that the OL performance is not influenced by increasing the temperature from 20°C to 100°C. The results obtained show the possibility of using the DNDs suspensions in engine oil as an optical limiter in a wide temperature range.

We present a study of resonant optical properties of paired silver hemispheroids grown on a glass substrate using out-diffusion technique combined with thermal poling of the glass. Atomic force microscopy was used to characterize the morphology of the grown nanostructures. Dark-field spectroscopy and numerical simulation were applied to study the optical properties of the coupled nanoparticles (NPs) depending on the interparticle gap and size difference of the hemispheroids in a pair. Raman spectroscopy testing of the coupled hemispherical NPs showed that they can provide signal enhancement factor exceeding one of a single hemispherical NP.

The ability of thin conductive films, including graphene, pyrolytic carbon (PyC), graphitic PyC (GrPyC), graphene with graphitic islands (GrI), glassy carbon (GC), and sandwich structures made of all these materials separated by polymer slabs to absorb electromagnetic radiation in microwave-THz frequency range, is discussed. The main physical principles making a basis for high absorption ability of these heterostructures are explained both in the language of electromagnetic theory and using representation of equivalent electrical circuits. The idea of using carbonaceous thin films as the main working elements of passive radiofrequency (RF) devices, such as shields, filters, polarizers, collimators, is proposed theoretically and proved experimentally. The important advantage of PyC, GrI, GrPyC, and GC is that, in contrast to graphene, they either can be easily deposited onto a dielectric substrate or are strong enough to allow their transfer from the catalytic substrate without a shuttle polymer layer. This opens a new avenue toward the development of a scalable protocol for cost-efficient production of ultralight electromagnetic shields that can be transferred to commercial applications. A robust design via finite-element method and design of experiment for RF devices based on carbon/graphene films and sandwiches is also discussed in the context of virtual prototyping.

The nanocomposites comprising of anatase titania nanoparticles uniformly distributed inside the porous carbon matrix were synthesized using furfuryl alcohol, tetrabutyltitanate, and nonionic surfactant. The characterization of the nanocomposite by scanning electron microscopy, transmission electron microscopy, energy dispersive x-ray analysis, x-ray diffractometry, and Raman spectroscopy revealed the formation of anatase titania nanoparticles of average sizes 10 to 20 nm. The observed broadening and blueshift of the main Raman peak of titanium dioxide nanoparticles were explained using the phonon confinement effect. The nanocomposite exhibited strong paramagnetism at low temperatures and was diamagnetic at higher temperatures, as well as a small contamination by magnetic impurities was detected. The paramagnetism originated from the amorphous defect-rich carbon and oxygen vacancies in titania.

We report on a saturable absorption in aqueous dispersions of nanodiamonds with femtosecond laser pulse excitation at a wavelength of 795 nm. The open aperture Z-scan experiments reveal that in a wide range of nanodiamond particle sizes and concentrations, a light-induced increase of transmittance occurs. The transmittance increase originates from the saturation of light absorption and is associated with a light absorption at 1.5 eV by graphite and dimer chains (Pandey dimer chains). The obtained key nonlinear parameters of nanodiamond dispersions are compared with those of graphene and carbon nanotubes, which are widely used for the mode-locking.

We report a similar feature in the response of resistor–memristor and capacitor–memcapacitor circuits with threshold-type memory devices driven by triangular waveform voltage. In both cases, the voltage across the memory device is stabilized during the switching of the memory device state. While in the memristive circuit this feature is observed when the applied voltage changes in one direction, the memcapacitive circuit with a ferroelectric memcapacitor demonstrates the voltage stabilization effect at both sweep directions. The discovered behavior of capacitor–memcapacitor circuit is also demonstrated experimentally. We anticipate that our observation can be used in the design of electronic circuits with emergent memory devices as well as in the identification and characterization of memory effects in threshold-type memory devices.

An experimental approach for the direct measurement of the circular photocurrent (CPC) has been developed. The method was tested for the measuring the CPC due to photon drag effect in the Ag/Pd nanocomposites film in a wide spectral range. Measurements were performed at the wavelengths of 266, 532, and 1064 nm. The experimental results were compared with those obtained by the indirect conventional scheme. The obtained results open a new possibility of application of the Ag/Pd nanocomposites film to determine the direction of the electric field vector rotation of elliptically polarized light.

The development of methods for in situ analysis is required to provide deeper understanding of carbon film materials formation during chemical vapor deposition (CVD). Here, we describe scanning probe microscope instrument designed for study of nucleation and growth of thin film materials obtained by carbon condensation from a hydrogen/methane gas mixture activated by the “hot filament” method. The microscope allows measurements of topology characteristics, width of band gap, Fermi level position, and electrical conductivity of the carbon film material during its formation in the CVD process. We present the design and the characteristics of the microscope in this paper.

The performance (PCE) of perovskite solar cells was investigated using the simulation programs solar cell capacitance simulator and analysis of microelectronic and photonic structures-1-D. This paper entailed a study of the effects of hole density concentrations, defect density, thickness of perovskite active layers, P3HT hole-transporting material (HTM) layer thickness, hole mobility, working temperature, and varying illumination intensity on the PCE, of open-circuit voltage, fill factor, short-circuit current density, and the simulation of J−V curves solar cells for varying illumination intensity. Then, J−V characteristics and quantum efficiency were calculated for different thickness absorbers and HTM layers. The simulation results showed an optimal value for the absorber layer thickness and for the HTM layer. Also, a rise in the temperature had a strong effect on the perovskite solar cells PCE. These simulation results serve to provide several important guidelines for feasible fabrication of higher-PCE perovskite solar cells.

The influence of chemical vapor deposition (CVD) graphene grain size on the electromagnetic (EM) shielding performance of graphene/polymethyl methacrylate (PMMA) multilayers in Ka-band was studied both experimentally and theoretically. We found that increasing the average graphene grain size from 20 to 400  μm does not change the EM properties of heterostructures consisting of graphene layers sandwiched between submicron thick PMMA spacers. The independence of EM interference shielding effectiveness on the graphene grain size between 20 and 400  μm allows one to use cheaper (or more convenient regimes of CVD) graphene samples with low crystallinity and small grain size in the development of new graphene-based passive EM devices operated at high frequencies.

Magnetic properties of graphene nanostructures functionalized with aromatic radicals were investigated by electron spin resonance (ESR) and superconducting quantum interference device (SQUID) techniques. Three types of functionalized graphene samples were investigated (functionalization was performed by 4-bromoaniline, 4-nitroaniline, or 4-chloroaniline). According to SQUID measurements, in case of functionalization by nitroaniline, sharp change in temperature dependence of magnetic susceptibility was observed near 120 K. Such behavior was explained as antiferromagnetic ordering. The same but more extended effect was observed in ESR measurements below 160 K. In the ESR measurements, only one resonance line with g-factor equal to 2.003 was observed. Based on the temperature dependencies of spin concentration and resonance position and intensity, the effect was explained as antiferromagnetic ordering along the extended defects on the basal planes of the graphene.

A metal-polymer nanocomposite of platinum–polyaniline (Pt/PANI) was deposited on fluorine-doped tin oxide glass substrates to function as a counter electrode for polysulfide redox reactions in cadmium sulfide quantum dot-sensitized solar cells. In addition, front-side illuminated photoelectrodes were sensitized by silver (Ag) nanoparticles (NPs) as an interfacial layer between a transparent conducting oxide substrate and a TiO₂ layer. This configuration, i.e., both the Pt/PANI counter electrode and the Ag NPs in the photoanode, leads to 1.92% in the power-conversion efficiency (PCE) of the fabricated cells. A PCE enhancement of around 21% was obtained for the Ag NPs-sensitized photoanodes, as compared with the Ag NPs-free one. The improved performance can be attributed to the easier transport of excited electrons and the inhibition of charge recombination due to the application of an Ag NPs layer. Electrochemical impedance spectroscopy measurements showed that once Ag NPs are incorporated in a photoanode, electron transport time decreases in the photoanode structure.

A photonic crystal fiber (PCF) structure in Ga–Sb–S-based chalcogenide glass has been designed for nonlinear applications. The propagation characteristics of the designed structure have been investigated by employing COMSOL multiphysics software based on a full-vectorial finite element method. The proposed PCF structure possesses a nonlinear coefficient as high as 14.92  W−¹ m−¹ with the effective mode area of 3.37  μm² at the operating wavelength of 1.55  μm. The proposed structure exhibits a flat and low dispersion value between spectral spanning 2.4 and 2.7  μm with a maximum dispersion variation of 20  ps/nm km. To the best of our knowledge, the PCF design is investigated for first time in Ga–Sb–S-based chalcogenide glass. The structure possesses a zero dispersion wavelength value at 2.6  μm. The structure is a promising candidate for nonlinear applications, such as midinfrared supercontinuum generation, slow-light generation, and midinfrared fiber lasers.

Plasmonic perfect absorbers are artificially designed metal-dielectric-metal (MDM) structures to realize unity optical absorption (UOA) at the specific spectral wavelength. In the recent past, a variety of structures have been investigated theoretically and experimentally to achieve UOA. However, fabrication of a complex structure often requires sophisticated instruments and skills. A simple structural design may be an alternative solution. An MDM structure consisting of a square array of cylindrical holes in the top layer is proposed, and optical reflection/absorption is studied using 3-D finite-difference time-domain computation to achieve UOA. The structure has three sequential layers: a ground gold plane (100-nm thick) to block the transmission, a spacer layer of typical thickness of 20 nm of constant real value of dielectric permittivity, and a top gold layer structured with periodic square array of cylindrical holes. Numerical results show period- and hole-depth-dependent 100% optical absorption (UOA) at a specific spectral wavelength. A significant influence of hole packing density and refractive index of filled material on the resonant absorption and absorption bandwidth is also observed. Based on the results, a design rule is proposed to achieve UOA at an arbitrarily chosen spectral wavelength in the visible range.

Relativistic quantum theory of induced scattering of two-dimensional Dirac particles by electrostatic field of an impurity ion (in the Born approximation) in the doped graphene in the presence of an external electromagnetic (EM) radiation field (actually terahertz radiation, to exclude the valence electrons excitations at high Fermi energies) has been developed. It is shown that the strong coupling of massless quasiparticles in the quantum nanostructures to a strong EM radiation field leads to the strong nonlinear response of graphene, which opens diverse ways for manipulating the electronic transport properties of conductive electrons by coherent radiation fields.

Broadband, all-angle negative refraction (AANR) effects and imaging with subwavelength resolution have been analyzed in a honeycomb lattice of silicon rods in air background, as well as in the inverse structure of air holes in a silicon wafer. In the rod lattice, it was possible to obtain AANR effects for transverse-magnetic (TM) polarization in the second band (TM2) with a bandwidth as large as ∼23% after optimizing the ratio of feature size to the lattice constant as 0.44 and a super-lensing effect with a binary coherent source resolution of 0.68λ. On the other hand, the hole lattice shows AANR for both TM2 (bandwidth of 14%) and TE2 (bandwidth of 15.3%) bands with an additional advantage of polarization-independent AANR of 5% bandwidth. The hole lattice also shows a super-lensing behavior, which helps in imaging with a subwavelength resolution of 0.19λ for a single-point source and 0.80λ with a binary source for TM polarization while it is 0.48λ and 0.97λ, respectively, for transverse-electric (TE) polarization. The conditions for perfect imaging have been studied, and the phenomenon of dual negative refraction for both TE and TM polarization is also discussed.

We focused on the optical properties of square array of subwavelength holes created within a titanium nitride (TiN) thin film. The TiN layer was placed on top of the dielectric layer as a surface plasmonic system originated from an intermetallic–dielectric arrangement. The finite-difference time-domain method was used via an Optiwave package to simulate periodic array of square and circular holes within the TiN layer. The effect of geometrical and material parameters such as periodic constant (a), size (S), shape of the holes, and the electric permittivity of the dielectric substrate has been investigated. An extraordinary optical transmission was observed in comparison with the nonhole system. It was shown that the wavelength of plasmonic modes, as a characteristic feature of the system, was affected by changing the periodic constant and electric permittivity. Meanwhile, changing the size as well as the shape of the holes did not affect the position of the peaks. These results are in agreement with the characteristic equation for plasmonic structure, which relates the surface plasmon wavelength (λ_sp) to the geometrical and material parameters of the system. The intensity of excited peaks was explained by distribution of the z-component of the electric field obtained from simulation, which illustrated the role of the surface plasmon polariton, localized surface plasmon resonance, and waveguide mode in tuning the optical behavior of the system. The results showed that TiN is a promising candidate for replacing metals in a plasmonic application with particular chemical and mechanical features.

Using the interference of N collimated laser beams, optical lattices with N-fold rotational symmetry are generated over the interface of two semi-infinite dielectric media. The interaction of small dielectric particles with these interference patterns is investigated using Rayleigh approximation. The polarization state of the interfering beams considerably influences the interference patterns and potential landscapes. Therefore, both parallel and perpendicular polarized interfering beams are considered and the corresponding potential profiles are compared and analyzed. We also study how the number of interfering waves, incident and azimuth angles, and initial phases of the incident beams influence optical lattices and potential profiles. It is found that the ring-shaped patterns with good confinement properties can be achieved by increasing the number of incident beams. In addition, by increasing the number of incident beams one can make an optical trap with sharper intensity gradient and deeper potential well, which is an advantage for trapping small Rayleigh particles. The lattices resulting from the interference of N incident waves with different incident angles are also investigated. Furthermore, the effects of changing the azimuth angles between two adjacent incident wave vectors on the intensity patterns are studied. The proposed configuration and the numerical results can find numerous applications in particle arrangement, particle sorting, and the creation of quasicrystals. We believe that interference approaches have many potential capabilities for molding light wavefronts and creating multiple traps with sophisticated patterns.

A wideband metamaterial (MTM) absorber based on a concentric ring resonator is discussed at visible frequencies. The proposed structure offers a wideband absorption response, where absorption of <70% is gained for the frequency ranging from 537.91 to 635.73 THz. The analysis is conducted on the components of the proposed structure to understand the origin of wideband absorption. Furthermore, a graphene monolayer sheet is integrated to the proposed MTM absorber to optimize its absorptivity, where the studies show enhancement of the absorptivity of the proposed structure up to 26% from its initial absorptivity. MTM absorbers of this kind have potential applications in solar cells.

Mn-doped zinc oxide (ZnO) nanostructures with different manganese concentrations along with high structural and optical quality were grown through a simple method without using any metal catalysts and through the source quantum dots of the nanowires (ZnO and MnO2). The cross section of the prepared nanowires has been a hexagon with a diameter between 35 and 50 nm and a length between 3 and 6  μm. The surface morphology of the samples was characterized by scanning electron microscopy. The results of the x-ray diffraction analysis showed the wurtzite structure for the prepared samples with a strong preferred peak (002). The energy dispersive x-ray spectra showed a high percentage of Mn at the tip of the samples, and the x-ray photoelectron spectroscopy showed the spectra of MnO2 in the structure of the nanowires. These wires produced a large PL emission peak in the ultraviolet (UV) region and a relatively high peak in the visible region. With the increase of the doping percentage, the intensity of the visible emission increased, and this amount reached to the highest peak intensity and maximum quantum yield (QY=39%) at 5% of the dopant as the quenching point. The UV peak of the Mn/ZnO nanowires amounts to 11-nm blueshifted with respect to pure ZnO nanowires confirmed by the UV–visible absorption spectra.

Use of dielectric nanoparticles placed at the anode (indium tin oxide) for the improvement of light-extraction efficiency of an organic light-emitting diode (OLED) has been reported. The nanoparticle layer will act as a scattering medium for the light trapped in the waveguiding modes of the device. Mie theory has been applied to study the scattering efficiency of the isolated dielectric nanoparticle. The effect of dielectric nanoparticles on the light-extraction efficiency of OLED has been analyzed by the finite-difference time-domain method. The light-extraction efficiency of the device depends upon the diameter, interparticle separation, and refractive index of dielectric nanoparticles. At optimal nanoparticle parameters, the enhancement factor of 1.7 times is obtained with the proposed design.

We numerically investigate the electromagnetically induced transparency (EIT) of a hybrid system consisting of a three-level quantum dot (QD) in the vicinity of vanadium dioxide nanoparticle (VO2NP). VO2NP has semiconductor and metallic phases where the transition between the two phases occurs around a critical temperature. When the QD-VO2NP hybrid system interacts with continuous wave laser fields in an infrared regime, it supports a coherent coupling of exciton–polariton and exciton–plasmon polariton in semiconductor and metal phases of VO2NP, respectively. In our calculations a filling fraction factor controls the VO2NP phase transition. A probe and control laser field configuration is studied for the hybrid system to measure the absorption of QD through the filling fraction factor manipulations. We show that for the VO2NP semiconductor phase and proper geometrical configuration, the absorption spectrum profile of the QD represents an EIT with two peaks and a clear minimum. These two peaks merge to one through the VO2NP phase transition to metal. We also show that the absorption spectrum profile is modified by different orientations of the laser fields with the axis of the QD-VO2NP hybrid system. The innovation in comparison to other research in the field is that robust variation in the absorption profile through EIT is due to the phase transition in VO2NP without any structural change in the QD-VO2NP hybrid system. Our results can be employed to design nanothermal sensors, optical nanoswitches, and energy transfer devices.

We design a solid hexagonal photonic crystal fiber (PCF) with air holes of different diameters in the cladding region using the finite element method. We achieve a low group velocity dispersion of −5.483  ps2/km and a high nonlinearity of 111.4  W−1  km−1 at 450 nm with d1/Λ being 0.345, which could ensure single-mode propagation. The low dispersion and high nonlinearity form the crucial requirements to generate the supercontinuum (SC) pulse. The designed PCF exhibits a broad SC spectrum of bandwidth 600 nm at an operating wavelength of 450 nm which might find a great relevance in optical sensing applications.

We propose and investigate a graphene-based resonator-coupled waveguide system comprising input/output graphene sheet bus waveguides and two graphene nanoribbon (GNR) resonators for bandpass spectral splitting. The system is composed of two graphene sheet waveguides and two GNRs located at the same side of the waveguides with different distances. The coupling between two GNRs results in the electromagnetically induced transparency effect and the bandpass spectral splitting. Moreover, benefiting from the chemical-potential-dependent optical properties of graphene, both the spectral symmetry and operation frequency can be dynamically adjusted, separately. The structure can find potential applications for integrated tunable functional devices such as filters and modulators.

A nonconcentric triple-microring resonator employing a silicon-on-insulator platform is proposed and analyzed for label-free sensing applications. The numerical simulations are carried out based on the finite-difference time-domain with perfectly matched layer boundary condition and transmission matrix methods. Its physical aspects and specific applications are highlighted. The results show that, in the optimized structure, a Q factor of 3.06×109 is achieved under weak coupling conditions. It is 3 orders of magnitude larger than that of a dual-ring resonator and 6 orders of magnitude larger than that of a single-ring resonator with lossless waveguide. In addition, to validate the proposed scheme, the designed ring resonator-based photonic sensor achieves refractive index sensing with resonance wavelength sensitivity of 101  nm/refractive index unit (RIU) and figure-of-merit of 11,211  RIU−1. Correspondingly, the detection limit of refractive index variation will be improved significantly compared with those of nonconcentric single-/dual-ring resonator and concentric triple-ring resonator. It is very useful for label-free on-chip biochemical sensing.

A transverse magnetic field in graphene, together with the high speed of Dirac electrons moving with Fermi velocity, gives rise to a set of collective modes, viz., kinetic magnetoplasmonic modes, two-dimensional equivalent of Bernstein modes, with frequencies in between the harmonics of electron cyclotron frequency. We develop a Vlasov theory of these modes in a moderate magnetic field, including finite gyroradius effects, and study their excitation by laser through linear mode conversion, facilitated by grating or periodic ribbons. At kρ→0 (where k is the wave number and ρ is the gyroradius of electrons), the magnetoplasmonic modes have frequencies near the harmonics of electron cyclotron frequency. The frequencies rise with wave number, attain maxima in the vicinity of the next cyclotron harmonic, and then fall off. In high-mobility graphene, with ribbons or grating of appropriate ripple wave number, a normally impinged laser coverts a significant fraction of its power into magnetoplasmons, reducing the laser transmissivity as observed in experiments.

In the race to realize ultrahigh-speed processors, silicon photonics research is part of the efforts. Overcoming the silicon indirect bandgap with special geometry, we developed a concept of a metal–oxide–semiconductor field-effect transistor, based on a silicon quantum well structure that enables control of light emission. This quantum well consists of a recessed ultrathin silicon layer, obtained by a gate-recessed channel and limited between two oxide layers. The device’s coupled optical and electrical properties have been simulated for channel thicknesses, varying from 2 to 9 nm. The results show that this device can emit near infrared radiation in the 1 to 2  μm range, compatible with the optical networking spectrum. The emitted light intensity can be electrically controlled by the drain voltage Vds while the peak emission wavelength depends on the channel thickness and slightly on Vds. Moreover, the location of the radiative recombination source inside the channel, responsible for the light emission, is also controllable through the applied voltages.

We propose a tunable, all-optical switch based on nonlinear photonic crystal ring resonators. Arrays of silver nanowires are embedded in the ring resonator to enhance the nonlinearity. Due to surface plasmon resonance and plasmonic field enhancement in the regions of metallic nanowires, the light intensity required for the operation of the proposed switch is reduced significantly. The minimum time and threshold power required to turn the switch on/off are ∼0.34  ps and 85  mW/μm2, respectively. The performance of the proposed switching structure is simulated by the finite-difference time-domain method in which the simulations indicate an ultracompact size structure with a promising ultrafast speed.

The unit cell of a chevronic sculptured thin film (ChevSTF) comprises two identical columnar thin films (CTFs) except that the nanocolumns of the first are oriented at an angle χ and nanocolumns of the second are oriented at an angle π−χ with respect to the interface of the two CTFs. A ChevSTF containing 10 unit cells was fabricated using resistive-heating physical vapor deposition of zinc selenide. Planewave reflectance and transmittance spectrums of this ChevSTF were measured for a wide variety of incidence conditions over the 500- to 900-nm range of the free-space wavelength. Despite its structural periodicity, the ChevSTF did not exhibit the Bragg phenomenon. Theoretical calculations with the CTFs modeled as biaxial dielectric materials indicated that the Bragg phenomenon would not be manifested for normal and near-normal incidence, but vestigial manifestation was possible for sufficiently oblique incidence. Thus, structural periodicity does not always lead to electromagnetic periodicity that underlies the exhibition of the Bragg phenomenon.

The random antireflective structures are modeled by the analysis of the random morphology distribution. According to the effective medium theory, the transmission of the antireflective structure is calculated by dividing the structure into multilayer, and the dependence on parameters of the subwavelength is analyzed in detail. In the single-variable condition, etching depth, half breadth of distribution, and median of distribution get a positive correlation with the transmittance where the etching depth plays a most important part in enhancing the transmittance, whereas the angle of structures gets a negative correlation. The experimental results coincide well with the calculation and analysis. The analysis offers a theory guidance to fabricate random subwavelength antireflected structures using metal dewetting.

We proposed a periodic coaxial honeycomb nanostructure array patterned in a silver film to realize the plasmonic structural color, which was inspired from natural honeybee hives. The spectral characteristics of the structure with variant geometrical parameters are investigated by employing a finite-difference time-domain method, and the corresponding colors are thus derived by calculating XYZ tristimulus values corresponding with the transmission spectra. The study demonstrates that the suggested structure with only a single layer has high transmission, narrow full-width at half-maximum, and wide color tunability by changing geometrical parameters. Therefore, the plasmonic colors realized possess a high color brightness, saturation, as well as a wide color gamut. In addition, the strong polarization independence makes it more attractive for practical applications. These results indicate that the recommended color-generating plasmonic structure has various potential applications in highly integrated optoelectronic devices, such as color filters and high-definition displays.

A broadband reflector for the near-infrared (NIR) was designed using a multilayer heterostructure consisting of several quarter-wave stacks (QWSs), which were composed of polymethyl methacrylate (PMMA) and polyethylene terephthalate (PET) films. Taking the solar power density as the target and using the Bragg wavelength of each QWS as the variable, the genetic algorithm was applied to look for the optimal multilayer heterostructure for broadband NIR reflection. As high as 99.46% total energy reflectivity in the short-wavelength NIR region (780 to 1100 nm) and 89.56% total energy transmissivity in the visible light region (380 to 780 nm) were realized by a multilayer heterostructure consisting of six quarter-wave PMMA/PET stacks, which can be easily fabricated based on the micronano multilayer coextrusion technology. The designed structure possesses good stability, and its total energy reflectivity is not sensitive to the incident angle of light. The proposed broadband NIR reflector can be applied to buildings as energy-saving films.

Currently, the method of choice to test for the presence of chromium in water is to submit samples to a lab for testing. We present a simple field-ready test that is selective for the presence of chromium at concentrations of 100 ppb or greater. The Environmental Protection Agency maximum contaminant level (MCL) for total chromium is 100 ppb. This test uses a simple on/off fluorescent screening employing the use of silver indium sulfide (AgInS2) quantum dots (QDs). These QDs were impregnated into cotton pads to simplify field testing without the need for solvents or other liquid chemicals to be present. The change in fluorescence is instant and can be readily observed by eye with the use of a UV flashlight.

This study experimentally demonstrates the feasibility of utilizing zinc oxide nanorods for CO and CO2 gas detection via optical scattering. ZnO nanorods are grown on a plastic optical fiber to measure the effect of gas flow on the optical scattering at room temperature. The presence of nanorods minimizes the coupling of the Fresnel reflection. Placing the optical setup in a home-built gas chamber, an obvious distinguished change of the total reflection was observed when different gas concentrations were present. Reduction of reflection due to the presence of gas indicated that forward scattering leak has a dominant effect on the process. In addition, the results demonstrated that detection of CO gas at a concentration as low as 200 ppm had a higher response in comparison with CO2 gas.

This erratum corrects an error in Fig. 2. The paper (doi: 10.1117/1.JNP.11.036001) was originally published on 6 July 2017.