Journal Sciences News
The Journal of Steroid Biochemistry and Molecular Biology
February 2018
Tunable wavelength demultiplexer using modified graphene plasmonic split ring resonators for terahertz communication
Publication date: February 2018
Source:Photonics and Nanostructures - Fundamentals and Applications, Volume 28 Author(s): Neetu Joshi, Nagendra P. Pathak This paper presents graphene modified ring resonator based wavelength demultiplexer (WDM) for THz device applications that is, a surface plasmon polaritons (SPPs) demultiplexer consisting of two nanostrip waveguides at input as well as output coupled to each other by a split ring resonator (SRR), which is modified in shape as compared to a simple ring-shaped resonator. A systematic analysis of the transmission spectra for the graphene based SRR poses clear insight on the demultiplexing phenomenon of the proposed nanodevice. The results show resonance peaks in the transmission spectrum, having a linear relationship with the chemical potential of graphene. The influence of structural parameters have also been analyzed. The tuning capability of graphene based tunable WDM, lays its foundation in the applications of optical switches, modulators, etc.
February 2018
Single-polarization operation in suspended-core microstructured fibers
Publication date: February 2018
Source:Photonics and Nanostructures - Fundamentals and Applications, Volume 28 Author(s): Yuan-Feng Zhu, Depeng Kong, Zhi-Qing Ye, Chun-Fang Rao, Hua Zhong We present the design and investigation of a single-polarization suspended-core fiber with an elliptical core consisting of crossed rectangular-shaped dielectric strips. By optimizing the fiber configuration parameters, single-polarization single-mode transmission with a bandwidth of 400nm can be obtained. Also, the power fraction in air of the x-polarization fundamental mode is relatively high, which facilitates its applications in high precision sensors.
February 2018
Properties of magnetic photonic crystals in the visible spectral region and their performance limitations
Publication date: February 2018
Source:Photonics and Nanostructures - Fundamentals and Applications, Volume 28 Author(s): V.A. Kotov, V.G. Shavrov, M. Vasiliev, K. Alameh, M. Nur-E-Alam, D.E. Balabanov We report on the results of computer modelling and performance analysis of the optical and magneto-optical (MO) characteristics of one-dimensional magnetic photonic crystals (MPC) of several classic design types (having either a single structure defect, or a number of these), designed for applications in the visible spectral region. The calculations are performed accounting for the real levels of optical absorption achievable in existing MO materials which currently demonstrate the best MO quality (bismuth-substituted ferrite garnets). We consider Bi2Dy1Fe4Ga1O12 as the base material for use within quarter-wave thick MO layers of MPC; silica is used for the non-magnetic transparent quarter-wave layers. The achieved results can be used to clarify the nature of the differences that exist between the expected practical potential of MPCs in integrated photonics, and the actual attained experimental results. Our results show that in MPCs optimized for light intensity modulation applications, in the red spectral region (near 650nm), the achievable levels of optical transmission are limited to about 30%. This coincides spectrally with the peaks of Faraday rotation reaching their maxima at about 25°, with further transmission increases possible in the near-infrared region. Larger Faraday rotation angles are only achievable currently in structures or single film layers with reduced transmission.
February 2018
Study of one-dimensional nanolayered graded photonic crystal consisting of birefringent and dielectric materials
Publication date: February 2018
Source:Photonics and Nanostructures - Fundamentals and Applications, Volume 28 Author(s): Rajeev Kumar, Dhananjay Kumar, Angad S. Kushwaha, S.K. Srivastava In the present paper, we have studied a comparison between dielectric-dielectric photonic crystal (PhC) and birefringent-dielectric PhC structure with, and without, gradation in the thickness of the layers of the proposed structure. Graded birefringent-dielectric PhC has a linear change in the thickness of the layers. With the help of the transfer matrix method, the proposed structures have been extensively investigated. It is found that photonic band gap (PBG) width and omnidirectional reflection band width has been widely enhanced, in graded birefringent-dielectric PhC structure as compared to the non-graded birefringent-dielectric PhC structure, for both TE and TM polarizations. We have also found that the gradation in the thickness of the birefringent layer is more effective, as compare the gradation in the thickness of the dielectric layer, for enhancement of reflection band width. The results obtained are quite good and thus, it may be widely used as broad band optical and omnidirectional reflector.
February 2018
Mid-infrared refractive index sensing using optimized slotted photonic crystal waveguides
Publication date: February 2018
Source:Photonics and Nanostructures - Fundamentals and Applications, Volume 28 Author(s): Lazhar Kassa-Baghdouche, Eric Cassan Slotted photonic crystal waveguides (SPCWs) were designed to act as refractive index sensing devices at mid-infrared (IR) wavelengths around
February 2018
Angle-resolved reflection spectroscopy of high-quality PMMA opal crystal
Publication date: February 2018
Source:Photonics and Nanostructures - Fundamentals and Applications, Volume 28 Author(s): Ivan V. Nemtsev, Igor A. Tambasov, Alexander A. Ivanenko, Victor Ya. Zyryanov PMMA opal crystal was prepared by a simple hybrid method, which includes sedimentation, meniscus formation and evaporation. We investigated three surfaces of this crystal by angle-resolved reflective light spectroscopy and SEM study. The angle-resolved reflective measurements were carried out in the 400–1100nm range. We have determined the high-quality ordered surface of the crystal region. Narrow particle size distribution of the surface has been revealed. The average particle diameter obtained with SEM was nearly 361 nm. The most interesting result was that reflectivity of the surface turned out up to 98% at normal light incidence. Using a fit of dependences of the maximum reflectivity wavelength from an angle based on the Bragg–Snell law, the wavelength of maximum 0° reflectivity, the particle diameter and the fill factor have been determined. For the best surface maximum reflectivity wavelength of a 0° angle was estimated to be 869 nm. The particle diameter and fill factor were calculated as 372nm and 0.8715, respectively. The diameter obtained by fitting is in excellent agreement with the particle diameter obtained with SEM. The reflectivity maximum is assumed to increase significantly when increasing the fill factor. We believe that using our simple approach to manufacture PMMA opal crystals will significantly increase the fabrication of high-quality photonic crystal templates and thin films.
February 2018
Tunable Fano resonance and high-sensitivity sensor with high figure of merit in plasmonic coupled cavities
Publication date: February 2018
Source:Photonics and Nanostructures - Fundamentals and Applications, Volume 28 Author(s): Yan Deng, Guangtao Cao, Hui Yang Actively tunable sharp asymmetric line shape and high-sensitivity sensor with high figure of merit (FOM) are analytically and numerically demonstrated in plasmonic coupled cavities. The Fano resonance, originating from the interference between different light pathways, is realized and effectively tuned in on-chip nanostructure composed of metal-dielectric-metal (MDM) waveguide and a pair of cavities. To investigate in detail the Fano line shape, the coupled cavities are taken as a composite cavity, and a dynamic theory is proposed, which agrees well with the numerical simulations. Subsequently, the sensing performances of the plasmonic structure is discussed and its detection sensitivity reaches 1.103
February 2018
Vertically emitting silicon disk resonators with periodic shape modulation
Publication date: February 2018
Source:Photonics and Nanostructures - Fundamentals and Applications, Volume 28 Author(s): Andrei Tsarev It is shown by direct numerical modeling, using the 3D FDTD method, that a disk resonator with a sinusoidal modulation of its boundary has not only a modified frequency spectrum, but also a greater proportion of its optical radiation is directed normal to its surface. Simulations are carried out for a set of disk resonators on a typical silicon-on-insulator structure with a 250-nm silicon core and a disk diameter of about 2.6
February 2018
Investigation of single-mode vertical-cavity surface-emitting lasers with graphene-bubble dielectric DBR
Publication date: February 2018
Source:Photonics and Nanostructures - Fundamentals and Applications, Volume 28 Author(s): Baolu Guan, Pengtao Li, Shamsul Arafin, Yazeed Alaskar, Kang L. Wang An inter-cavty contact single mode 850nm VCSEL was fabricated with a graphene assisted self-assembly curved dielectric bubble Bragg mirror for the first time. Taking the advantage of graphene’s uniform low surface energy, the low cost dielectric bubble DBR (Si3N4/SiO2) was deposited on top of the graphene/half-VCSEL structure via van der Waals Force (vdWF) without using any additional spacing elements and sacrificial layer release-etch process. The continuous-wave operating VCSELs with an aperture diameter of 7
February 2018
Photonic crystal double-coupled cavity waveguides and their application in design of slow-light delay lines
Publication date: February 2018
Source:Photonics and Nanostructures - Fundamentals and Applications, Volume 28 Author(s): Mohammad Danaie, Alireza Geravand, Saeed Mohammadi In this paper the idea of double-coupled cavity waveguides is introduced. The cavities used in this paper support two orthogonal degenerate resonance modes. These cavities are coupled together both horizontally and vertically. The obtained matrix of cavities introduces many interesting properties for design of photonic crystal devices such as phase shifters and gates. As an application, it is shown that the coupled matrix of cavities can be used for design of ultra-compact slow-light photonic crystal optical delay lines. Finite difference time domain method and plane wave expansion method are used to analyze the structures.
February 2018
Inclusion of Indium, with doping in the barriers of InxGa1-xN/InyGa1-yN quantum wells reveals striking modifications of the emission properties with current for better operation of LEDs
Publication date: February 2018
Source:Photonics and Nanostructures - Fundamentals and Applications, Volume 28 Author(s): Anup Gorai, Apu Mistry, Siddhartha Panda, Dipankar Biswas Although that the continuous tunability of InGaN/GaN QW LEDs, carries the promise of a significant impact in optoelectronics, the reduction of the square of the overlap of electron and hole wave functions ($M e h 2$) in InGaN/GaN QW LEDs, under certain conditions, is a sizable problem, difficult to overcome. Theoretical investigations have been carried out on the incorporation of Indium (In) in the GaN barrier layers, with an aim of increasing the overlap of electron and hole wave functions. Rigorous studies through the self consistent solution of Schr
February 2018
Ultra-photo-stable coherent random laser based on liquid waveguide gain channels doped with boehmite nanosheets
Publication date: February 2018
Source:Photonics and Nanostructures - Fundamentals and Applications, Volume 28 Author(s): Hua Zhang, Hong Zhang, Chao Yang, Jiangyun Dai, Jiajia Yin, Hongyan Xue, Guoying Feng, Shouhuan Zhou Construction of ultra-photo-stable coherent random laser based on liquid waveguide gain channels doped with boehmite nanosheets has been demonstrated. An Al plate uniformly coated with boehmite nanosheets was prepared by an alkali-treatment method and used as a scattering surface for the coherent random laser. Microcavity may be formed between these boehmite nanosheets owing to the strong optical feedback induced by the multiple light scattering. Many sharp peaks are observed in the emission spectra, and their laser thresholds are different, which confirms the feedback mechanism is coherent. The linewidth of the main peak at 571.74
February 2018
Silver films over silica microspheres (AgFOSM) as SERS substrates
Publication date: February 2018
Source:Photonics and Nanostructures - Fundamentals and Applications, Volume 28 Author(s): E. Flores-Romero, E. Rodr
February 2018
A simple homogeneous model for regular and irregular metallic wire media samples
Publication date: February 2018
Source:Photonics and Nanostructures - Fundamentals and Applications, Volume 28 Author(s): S.Y. Kosulnikov, M.S. Mirmoosa, C.R. Simovski To simplify the solution of electromagnetic problems with wire media samples, it is reasonable to treat them as the samples of a homogeneous material without spatial dispersion. The account of spatial dispersion implies additional boundary conditions and makes the solution of boundary problems difficult especially if the sample is not an infinitely extended layer. Moreover, for a novel type of wire media – arrays of randomly tilted wires – a spatially dispersive model has not been developed. Here, we introduce a simplistic heuristic model of wire media samples shaped as bricks. Our model covers WM of both regularly and irregularly stretched wires.
Available online 11 January 2018
Simulation and analysis of plasmonic sensor in NIR with fluoride glass and graphene layer
Publication date: February 2018
Source:Photonics and Nanostructures - Fundamentals and Applications, Volume 28 Author(s): Ankit Kumar Pandey, Anuj K. Sharma A calcium fluoride (CaF2) prism based plasmonic biosensor with graphene layer is proposed in near infrared region (NIR) of operation. The stacking of multilayer graphene is considered with dielectric interlayer sandwiched between two graphene layers. Excellent optical properties of CaF2 glass and enhanced field at the graphene-analyte interface are intended to be exploited for proposed sensor structure in NIR spectral region. Performance parameters in terms of field enhancement at interface and figure of merit (FOM) are analyzed and compared with those of conventional SPR based sensor. It is demonstrated that the same sensor probe can also be used for gas sensing with nearly 3.5–4 times enhancement in FOM, compared with conventional sensor. The results show that CaF2 based SPR sensor provides much better sensitivity than that based on other glasses.
Available online 10 January 2018
Brillouin gain enhancement in nano-scale photonic waveguide
Publication date: Available online 11 January 2018
Source:Photonics and Nanostructures - Fundamentals and Applications Author(s): Soodabeh Nouri Jouybari The enhancement of stimulated Brillouin scattering in nano-scale waveguides has a great contribution in the improvement of the photonic devices technology. The key factors in Brillouin gain are the electrostriction force and radiation pressure generated by optical waves in the waveguide. In this article, we have proposed a new scheme of nano-scale waveguide in which the Brillouin gain is considerably improved compared to the previously-reported schemes. The role of radiation pressure in the Brillouin gain was much higher than the role of the electrostriction force. The Brillouin gain strongly depends on the structural parameters of the waveguide and the maximum value of 12127
November 2017
Gold Nanoparticle Plasmon Resonance in Near-Field Coupled Au NPs layer/Al Film Nanostructure: Dependence on Metal Film Thickness
Publication date: Available online 10 January 2018
Source:Photonics and Nanostructures - Fundamentals and Applications Author(s): Oleg A. Yeshchenko, Viktor V. Kozachenko, Antonina P. Naumenko, Nataliya I. Berezovska, Nataliya V. Kutsevol, Vasyl A. Chumachenko, Michael Haftel, Anatoliy O. Pinchuk We study the effects of coupling between plasmonic metal nanoparticles and a thin metal film by using light extinction spectroscopy. A planar monolayer of gold nanoparticles located near an aluminum thin film (thicknesses within the range of 0–62
November 2017
Analysis of light propagation in quasiregular and hybrid Rudin–Shapiro one-dimensional photonic crystals with superconducting layers
Publication date: November 2017
Source:Photonics and Nanostructures - Fundamentals and Applications, Volume 27 Author(s): H.A. G
November 2017
All-angle negative refraction flatlens with a broad bandwidth
Publication date: November 2017
Source:Photonics and Nanostructures - Fundamentals and Applications, Volume 27 Author(s): Shuo Li, Fei Meng, Han Lin, Xiaodong Huang, Baohua Jia All-angle negative refraction (AANR) contributes to a subwavelength imaging with the ability to collect light from all incident angles to generate negative refraction. However, it is challenging to realize a broadband AANR with the conventional photonic crystal (PhC) structures due to the dispersion nature, which makes the refracted light highly sensitive to the incident angle. In this work broadband AANR PhCs are proposed based on the supercircle void or rod design, for transverse electric (TE) and transverse magnetic (TM) polarizations respectively. By adjusting the filling ratio of the dielectric material, the nearly optimal AANR range is realized. Flat lenses based on the supercircle designs are able to form subwavelength imaging in a frequency range 3 times broader than the state-of-the-art for TE polarization and 1.1 times for TM polarization, respectively.
November 2017
Manipulating the optical properties of dual implanted Au and Zn nanoparticles in sapphire
Publication date: November 2017
Source:Photonics and Nanostructures - Fundamentals and Applications, Volume 27 Author(s): E.N. Epie, D. Scott, W.K. Chu We have synthesized and manipulated the optical properties of metallic nanoparticles (NPs) by using a combination of low-energy high-fluence dual implantation and thermal annealing. We demonstrated that by implanting Zn before Au, the resulting absorption peak is enormously blue-shifted by 120nm with respect to that of Au-only implanted samples. This magnitude of optical shift is not characteristic of unalloyed Au and to the best of our knowledge cannot be attributed to NP size change alone. On the other hand, the absorption peak for samples implanted with Au followed by Zn is blue-shifted about 20nm. Additionally, by carefully annealing all implanted samples, both NP size distribution and corresponding optical properties can be further modified in a controlled manner. We attribute these behaviours to nanoalloy formation. This work provides a direct method for synthesizing and manipulating both the plasmonic and structural properties of metallic alloy NP in various transparent dielectrics for diverse applications.
November 2017
The effect of the local field and dipole-dipole interactions on the absorption spectra of noble metals and the plasmon resonance of their nanoparticles
Publication date: November 2017
Source:Photonics and Nanostructures - Fundamentals and Applications, Volume 27 Author(s): I.I. Shaganov, T.S. Perova, K. Berwick An analysis of the effect of free and bound electrons on the optical properties of noble metals and their nanoparticles is performed, based on the Drude-Lorentz model. It is shown that the shifts in the absorption bands of plasmons localized in spherical nanoparticles with respect to the zero frequency of free electrons in a bulk metal can be estimated using the theory of resonant dipole-dipole interactions. The calculation includes account for differences between the effective and average electromagnetic fields. It is established that the difference in oscillator strength for free electrons in the bulk metal, obtained using the Drude-Lorentz model, and the microscopic oscillators in the corresponding spherical nanoparticle, is due to background polarization. This occurs at the expense of high-frequency excitation of the bound electrons. These results show that interparticle interactions in the noble metals in the quasi-static approximation can be regarded as dipole-dipole interactions of point dipoles with a concentration equal to the concentration of free electrons.
November 2017
Subwavelength gratings for polarization conversion and focusing of laser light
Publication date: November 2017
Source:Photonics and Nanostructures - Fundamentals and Applications, Volume 27 Author(s): Sergey S. Stafeev, Victor V. Kotlyar, Anton G. Nalimov, Maria V. Kotlyar, Liam O’Faolain We review thin micro-optics components with nanostructured microreliefs intended to control the polarization and phase of laser light. These components include transmission and reflection subwavelength diffraction gratings characterized by spatially
November 2017
Analysis of extraction routes in surface textured thin-film optical emitters with transparent substrates
Publication date: November 2017
Source:Photonics and Nanostructures - Fundamentals and Applications, Volume 27 Author(s): Jin-Young Na, Yoon-Jong Moon, Ji-Hyun Kim, Dukkyu Bae, Sun-Kyung Kim We propose a systematic strategy that enables analysis of the outcoupling efficiency through each extraction route for two-dimensional (2D) patterned thin-film optical emitters with transparent substrates. Full-vectorial simulations combined with the near-to-far-field transformations are applied to quantitatively analyze the extraction routes of blue-emitting InGaN/GaN light-emitting diodes (LEDs) on 2D patterned sapphire substrate, from which the main extraction routes are through the top and side surfaces of the substrate. For patterned sapphire substrates, the ratio of top to side emission is calculated for various lattice constants (a) of the pattern; for example, the efficiencies through the top and side routes are nearly equal at a =3000nm. We find that the top extraction of light is dramatically improved by increasing the index contrast in patterned substrates, suggesting high-index-contrast patterned substrates containing hollow cavities. The dramatic enhancement in top emission is verified by measuring the far-field distribution of InGaN/GaN LED devices fabricated on sapphire substrate containing hollow cavities and reference patterned sapphire substrate. The simulation algorithm studied herein will provide valuable design freedom for thin-film optical emitters such as GaN-based LEDs and organic LEDs.
November 2017
Magneto-optical Faraday effect in suspended core micro-structured optical fiber filled with magnetic CoFe2O4 nanoparticles doped composite material
Publication date: November 2017
Source:Photonics and Nanostructures - Fundamentals and Applications, Volume 27 Author(s): D. Jamon, E. Marin, S. Neveu, M.-F. Blanc-Mignon, F. Royer This paper deals with the study of the magneto-optical Faraday effect of micro-structured optical fibers with suspended cores covered by a silica matrix doped by CoFe2O4 nanoparticles. Two different size distributions of nanoparticles originated from two magnetic fluids have been used to dope a sol-gel preparation later introduced in the fiber. Faraday rotation measurements were performed in liquid state, thin film and finally in the fiber in guided configuration. The two different magnetic behaviors of these nanoparticles collections allow us to evidence the Faraday effect of the micro-structured optical fiber.
Available online 31 October 2017
All-optical photonic crystal logic gates using nonlinear directional coupler
Publication date: November 2017
Source:Photonics and Nanostructures - Fundamentals and Applications, Volume 27 Author(s): Hojjat Sharifi, Seyedeh Mehri Hamidi, Keivan Navi In this paper, a nonlinear photonic crystal structure consisting of a nonlinear directional coupler and junctions for the design of all-optical logic gates is proposed. A bi-functional photonic crystal structure is initially designed which provides different two XOR or OR logic operations. Thereafter, by applying some modifications in the basic structure, new topologies for all-optical XNOR, NOR and AND logic gates are proposed. Nonlinear rods of the proposed structure are made of silicon nanocrystal to create required phase shift. The finite difference time domain and plane wave expansion methods are used to evaluate the proposed structures. Our simulation results show that the proposed gates can operate with a bit rate of more than 1 Tbits/s and also, inputs and output of the proposed logic gates are homogeneous with the required power of 3W for switching operation.
September 2017
Effects of optical absorption in deep ultraviolet nanowire light-emitting diodes
Publication date: Available online 31 October 2017
Source:Photonics and Nanostructures - Fundamentals and Applications Author(s): M. Djavid, D.D. Choudhary, M. Rajan Philip, T.H.Q. Bui, O. Akinnuoye, T.T. Pham, H.P.T. Nguyen We report our study on the effect of optical absorption in nanowire ultraviolet light-emitting diodes (LEDs) using three-dimensional finite difference time domain simulation. Utilizing nanowire structures can avoid the emission of guided modes inside LED structure and redirect the trapped light into radiated modes. The optical loss due to material absorption can be decreased by reducing light propagation path inside the LED structure, and consequently enhance the light extraction efficiency (LEE). Nanowire form factors including size, and density play important roles on the LEE of ultraviolet (UV) nanowire LEDs. In this paper, the nanowire spacing and diameter are considered in simulation to reach maximum LEE. Our results show an unprecedentedly high LEE of
September 2017
Theoretical designs for novel photonic crystal nanocavities with Si (111) interfaces
Publication date: September 2017
Source:Photonics and Nanostructures - Fundamentals and Applications, Volume 26 Author(s): Alyssa Prasmusinto, Mo
September 2017
On corrected formula for irradiated graphene quantum conductivity
Publication date: September 2017
Source:Photonics and Nanostructures - Fundamentals and Applications, Volume 26 Author(s): N.E. Firsova Graphene membrane irradiated by weak activating periodic electric field in terahertz range is considered. The corrected formula for the graphene quantum conductivity is found. The obtained formula gives complex conjugate results when radiation polarization direction is clockwise or it is opposite clockwise. The found formula allows us to see that the graphene membrane is an oscillating contour. Its eigen frequency coincides with a singularity point of the conductivity and depends on the electrons concentration. So the graphene membrane could be used as an antenna or a transistor and its eigen frequency could be tuned by doping in a large terahertz-infrared frequency range. The obtained formula allows us also to calculate the graphene membrane quantum inductivity and capacitance. The found dependence on electrons concentration is consistent with experiments. The method of the proof is based on study of the time-dependent density matrix. The exact solution of von Neumann equation for density matrix is found for our case in linear approximation on the external field. On this basis the induced current is studied and then the formula for quantum conductivity as a function of external field frequency and temperature is obtained. The method of the proof suggested in this paper could be used to study other problems. The found formula for quantum conductivity can be used to correct the SPPs Dispersion Relation and for the description of radiation process. It would be useful to take the obtained results into account when constructing devices containing graphene membrane nanoantenna. Such project could make it possible to create wireless communications among nanosystems. This would be promising research area of energy harvesting applications.
September 2017
Designing of highly birefringence, dispersion shifted decagonal photonic crystal fiber with low confinement loss
Publication date: September 2017
Source:Photonics and Nanostructures - Fundamentals and Applications, Volume 26 Author(s): Moutusi De, Rahul Kumar Gangwar, Vinod Kumar Singh In this article we propose a decagonal photonic crystal fiber (D-PCF) consisting unique cladding without structural complexity having very high birefringent of the order of 10
September 2017
Nonclassical light sources for silicon photonics
Publication date: September 2017
Source:Photonics and Nanostructures - Fundamentals and Applications, Volume 26 Author(s): Daniele Bajoni, Matteo Galli Quantum photonics has recently attracted a lot of attention for its disruptive potential in emerging technologies like quantum cryptography, quantum communication and quantum computing. Driven by the impressive development in nanofabrication technologies and nanoscale engineering, silicon photonics has rapidly become the platform of choice for on-chip integration of high performing photonic devices, now extending their functionalities towards quantum-based applications. Focusing on quantum Information Technology (qIT) as a key application area, we review recent progress in integrated silicon-based sources of nonclassical states of light. We assess the state of the art in this growing field and highlight the challenges that need to be overcome to make quantum photonics a reliable and widespread technology.
September 2017
Tuning light concentration inside plasmonic core-shell nanoparticles during laser irradiation
Publication date: September 2017
Source:Photonics and Nanostructures - Fundamentals and Applications, Volume 26 Author(s): L.G. Astafyeva, V.K. Pustovalov, W. Fritzsche Computer modeling was carried out of the intensity distributions of optical (laser) radiation with wavelengths in the range of 180–540nm concentrated inside spherical two-layered core-shell nanoparticles with the core radii in the range 10–30nm and shell thicknesses range 5–40nm during irradiation. Different metals and oxides are used for core and shell materials of nanoparticles. Novel effect of light localizing at the nanoscale inside spherical two-layered core-shell NPs has been established on the base of computer calculations in the frame of the theory of diffraction of electromagnetic radiation on multilayer sphere. Light intensity concentrates in shadow hemisphere of core-shell NPs for the selected values of nanoparticle sizes and radiation wavelengths. These results can be applied in nanophotonics for construction of novel plasmonic devices and photonic components, and for different applications of the core-shell nanoparticles.
September 2017
Linear electromagnetic wave equations in materials
Publication date: September 2017
Source:Photonics and Nanostructures - Fundamentals and Applications, Volume 26 Author(s): R. Starke, G.A.H. Schober After a short review of microscopic electrodynamics in materials, we investigate the relation of the microscopic dielectric tensor to the current response tensor and to the full electromagnetic Green function. Subsequently, we give a systematic overview of microscopic electromagnetic wave equations in materials, which can be formulated in terms of the microscopic dielectric tensor.
September 2017
Optically driven random lasing in ZnO nanorods prepared by chemical bath deposition
Publication date: September 2017
Source:Photonics and Nanostructures - Fundamentals and Applications, Volume 26 Author(s): W. Maryam, N. Fazrina, M.R. Hashim, H.C. Hsu, M.M. Halim In this paper, we report on room temperature UV lasing emission observed in a mirror-less ZnO sample prepared by two-step chemical bath deposition technique; a popular low cost method for making ZnO nanorods. We attribute the mechanism of the laser emission to coherent multiple light scattering between the nanorods within the illuminated area of excitation. Reduced threshold condition was observed for the nanorods having smallest crystallite size. Furthermore, the ability to maintain the number of modes at different excitation areas of the sample as well as at different pump powers suggests this method of growing the ZnO nanorods as a promising growth method for industry in developing high efficiency low cost random lasers for future integrated photonic devices.

### Graphical abstract

September 2017
Photonic crystal optofluidic biolaser
Publication date: September 2017
Source:Photonics and Nanostructures - Fundamentals and Applications, Volume 26 Author(s): Mohammad Hazhir Mozaffari, Majid Ebnali-Heidari, Gholamreza Abaeiani, Mohammad Kazem Moravvej-Farshi Optofluidic biolasers are recently being considered in bioanalytical applications due to their advantages over the conventional biosensing methods Exploiting a photonic crystal slab with selectively dye-infiltrated air holes, we propose a new optofluidic heterostructure biolaser, with a power conversion efficiency of 25% and the spectral linewidth of 0.24nm. Simulations show that in addition to these satisfactory lasing characteristics, the proposed lab-on-a-chip biolaser is highly sensitive to the minute biological changes that may occur in its cavity and can detect a single virus with a radius as small as 13nm.

### Graphical abstract

September 2017
Tunable focusing by a flexible metasurface
Publication date: September 2017
Source:Photonics and Nanostructures - Fundamentals and Applications, Volume 26 Author(s): Yair Z
September 2017
Intensity-based readout of resonant-waveguide grating biosensors: Systems and nanostructures
Publication date: September 2017
Source:Photonics and Nanostructures - Fundamentals and Applications, Volume 26 Author(s): Moritz Paulsen, Sabrina Jahns, Martina Gerken Resonant waveguide gratings (RWG)
July 2017
Application of graphene second-order nonlinearity in THz plasmons excitation
Publication date: September 2017
Source:Photonics and Nanostructures - Fundamentals and Applications, Volume 26 Author(s): Kamal Jamalpoor, Abbas Zarifkar, Mehdi Miri In this paper, the phase-matching condition, the excited electric field formula, and the nonlinear susceptibility tensor elements conditions required for excitation of surface plasmon polaritons (SPPs) on flat graphene are derived. The second-order nonlinearity is utilized for compensation of the free-space and SPPs wave vectors mismatch. In order to excite SPPs on graphene, the phase matching condition is investigated for the second-order effects including the difference frequency generation (DFG), the second harmonic generation (SHG), and the sum-frequency generation (SFG). In addition, since the incident waves polarizations play an important role in the excitation of the SPPs, the realization of the susceptibility tensor elements conditions, the effect of TE, TM, not polarized and perpendicularly polarized incident waves are investigated using the Green’s function theory.
July 2017
Investigation of dynamical characteristics and modulation response function of InAs/InP (311)B quantum dot lasers with different QD size
Publication date: July 2017
Source:Photonics and Nanostructures - Fundamentals and Applications, Volume 25 Author(s): Kaveh Kayhani, Esfandiar Rajaei We have investigated the effect of size of InAS/InP (311)B quantum dot (QD), both height an diameter, on electronic levels and hence transition energies through k.p model, with focus on application in QD lasers. Therefore the results have been included in dynamic analysis based on coupled differential rate equations, to obtain variation of laser properties such as gain, photon number and modulation bandwidth in accordance to different experimental outcomes. This demonstrates that larger modulation bandwidth of ground state is given by QDs with smaller diameter but larger height however for excited state larger modulation bandwidth is given by smaller diameter and smaller height.
July 2017
Design of novel SOI 1
July 2017
Two dimensional tunable photonic crystal defect based drop filter at communication wavelength
Publication date: July 2017
Source:Photonics and Nanostructures - Fundamentals and Applications, Volume 25 Author(s): Nirmala Maria D'souza, Vincent Mathew We propose a two dimensional photonic crystal (PhC) based drop filter, at communication wavelength with more than 90% transmission. The filtering is achieved by introducing two line defects and three point defects in a two dimensional triangular array of ferroelectric rods in air. Using the electro-optic property of the ferroelectric, about 32nm tuning in the resonance wavelength is obtained. For the calculation of transmission, finite difference time domain (FDTD) simulations were performed. The operating frequency range is explored via the band structure which is obtained by the implementation of plane wave expansion (PWE) method. The influence of the radius of various rods on the filter wavelength as well as efficiency is also analyzed. The different possible configurations of this filter are also considered.
July 2017
Ultra-flattened nearly-zero dispersion and ultrahigh nonlinear slot silicon photonic crystal fibers with ultrahigh birefringence
Publication date: July 2017
Source:Photonics and Nanostructures - Fundamentals and Applications, Volume 25 Author(s): Jianfei Liao, Yingmao Xie, Xinghua Wang, Dongbo Li, Tianye Huang A slot silicon photonic crystal fiber (PCF) is proposed to simultaneously achieve ultrahigh birefringence, large nonlinearity and ultra-flattened nearly-zero dispersion over a wide wavelength range. By taking advantage on the slot effect, ultrahigh birefringence up to 0.0736 and ultrahigh nonlinear coefficient up to 211.48W
July 2017
New generation of one-dimensional photonic crystal cavities as robust high-efficient frequency converter
Publication date: July 2017
Source:Photonics and Nanostructures - Fundamentals and Applications, Volume 25 Author(s): T.S. Parvini, M.M. Tehranchi, S.M. Hamidi An effective method is proposed to design finite one-dimensional photonic crystal cavities (PhCCs) as robust high-efficient frequency converter. For this purpose, we consider two groups of PhCCs which are constructed by stacking m nonlinear (LiNbO3) and n linear (air) layers with variable thicknesses. In the first group, the number of linear layers is less than the nonlinear layers by one and in the second group by two. The conversion efficiency is calculated as a function of the arrangement and thicknesses of the linear and nonlinear layers by benefiting from nonlinear transfer matrix method. Our numerical simulations show that for each group of PhCCs, there is a structural formula by which the configurations with the highest efficiency can be constructed for any values of m and n (i.e. any number of layers). The efficient configurations are equivalent to Fabry–P
July 2017
Polymer electro-optic modulator efficiency enhancement by the high permittivity dielectric strips
Publication date: July 2017
Source:Photonics and Nanostructures - Fundamentals and Applications, Volume 25 Author(s): Andrei Tsarev, Rinat Taziev, Evan Heller, Maryvonne Chalony The performance improvement of rib-waveguide electro-optic (EO) polymer modulators resulting from the inclusion of high permittivity dielectric strips is considered. For this study, we take into account the heterogeneous nature of the poling of the electro-optic polymer by the electrode structure, the dispersion of the RF wave due to the material dispersion in the waveguide, and the finite conductivity of the electrodes. It is shown that the insertion of additional insulating strips with high dielectric permittivity (such as MgO) considerably enhances (from 120% to 280%) the efficiency of EO tuning. Furthermore, this efficiency grows with increasing modulation frequency, yielding a 2.0V half-wave voltage at 100GHz, when DH-80 EO polymer is used.

### Graphical abstract

July 2017
Effect of calcination temperature on structure and photocatalytic activity under UV and visible light of nanosheets from low-cost magnetic leucoxene mineral
Publication date: July 2017
Source:Photonics and Nanostructures - Fundamentals and Applications, Volume 25 Author(s): Wissanu Charerntanom, Wisanu Pecharapa, Suttipan Pavasupree, Sorapong Pavasupree This research has experimentally synthesized the nanosheets from the naturally-mineral magnetic leucoxene under the hydrothermal synthesis condition of 105°C for 24h. Magnetic leucoxene was utilized as the starting material due to its high TiO2 content (70–80%) and inexpensiveness. The characterization of the synthesized nanosheets was subsequently carried out: the crystalline structure, the chemical composition, the shape, the size and the specific surface area, by the X-ray diffraction (XRD), X-ray fluorescence (XRF), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and Brunauer–Emmett–Teller (BET) specific surface area analysis. The analysis results indicated that the starting magnetic leucoxene is of rutile phase while the synthesized nanosheets are of titanate structure (H2Ti x O2x +1). After calcination at the temperature range of 300 and 400°C, the calcined samples demonstrated TiO2 (B). At 500 and 600°C, the calcined nanosheets revealed a bi-crystalline mixture consisting of TiO2 (B) and anatase TiO2. At 700–1000°C, the crystalline structure shows anatase and rutile phase. At 1100°C, the prepared samples consisted of a mixture of anatase, rutile phase of TiO2, and Fe2O3 phase. The synthesized product also exhibited the flower-like morphology with 2–5
July 2017
Enhanced geometries of macroporous silicon photonic crystals for optical gas sensing applications
Publication date: July 2017
Source:Photonics and Nanostructures - Fundamentals and Applications, Volume 25 Author(s): D. Cardador, D. Vega, D. Segura, T. Trifonov, A. Rodr
July 2017
Numerical studies on a plasmonic temperature nanosensor based on a metal-insulator-metal ring resonator structure for optical integrated circuit applications
Publication date: July 2017
Source:Photonics and Nanostructures - Fundamentals and Applications, Volume 25 Author(s): Md. Jubayer Al-mahmod, Rakib Hyder, Md Zahurul Islam A nanosensor, based on a metal-insulator-metal (MIM) plasmonic ring resonator, is proposed for potential on-chip temperature sensing and its performance is evaluated numerically. The sensor components can be fabricated by using planar processes on a silicon substrate, making its manufacturing compatible to planar electronic fabrication technology. The sensor, constructed using silver as the metal rings and a thermo-optic liquid ethanol film between the metal layers, is capable of sensing temperature with outstanding optical sensitivity, as high as
July 2017
Optical properties of one-dimensional photonic crystals containing graphene-based hyperbolic metamaterials
Publication date: July 2017
Source:Photonics and Nanostructures - Fundamentals and Applications, Volume 25 Author(s): Amir Madani, Samad Roshan Entezar The transmission properties of a one-dimensional photonic crystal made of alternate layers of an isotropic ordinary dielectric and a graphene-based hyperbolic metamaterial are studied theoretically using the transfer matrix method. The metamaterial layers show hyperbolic dispersion in certain frequency range and are considered as an anisotropic effective medium in which the optical axis is normal to the graphene layers. It is shown that the structure has some photonic band gaps in both the hyperbolic and elliptical frequency regions of the hyperbolic metamaterial layers, which are tunable by changing the chemical potential of the graphene monolayers. Moreover, the characteristics of the transverse-magnetic (TM)-polarized photonic band gaps remarkably depend on the orientation of the optical axis of the hyperbolic metamaterial layers. It is found that the electric field intensity of the propagating modes from the hyperbolic metamaterial frequency region is concentrated in the high-index isotropic layers and the electric field intensity of the propagating modes from the elliptical frequency region is concentrated in the low-index anisotropic layers.
July 2017
Au coated PS nanopillars as a highly ordered and reproducible SERS substrate
Publication date: July 2017
Source:Photonics and Nanostructures - Fundamentals and Applications, Volume 25 Author(s): Yong-Tae Kim, Joerg Schilling, Stefan L. Schweizer, Guido Sauer, Ralf B. Wehrspohn Noble metal nanostructures with nanometer gap size provide strong surface-enhanced Raman scattering (SERS) which can be used to detect trace amounts of chemical and biological molecules. Although several approaches were reported to obtain active SERS substrates, it still remains a challenge to fabricate SERS substrates with high sensitivity and reproducibility using low-cost techniques. In this article, we report on the fabrication of Au sputtered PS nanopillars based on a template synthetic method as highly ordered and reproducible SERS substrates. The SERS substrates are fabricated by anodic aluminum oxide (AAO) template-assisted infiltration of polystyrene (PS) resulting in hemispherical structures, and a following Au sputtering process. The optimum gap size between adjacent PS nanopillars and thickness of the Au layers for high SERS sensitivity are investigated. Using the Au sputtered PS nanopillars as an active SERS substrate, the Raman signal of 4-methylbenzenethiol (4-MBT) with a concentration down to 10
May 2017
Engineering two-wire optical antennas for near field enhancement
Publication date: July 2017
Source:Photonics and Nanostructures - Fundamentals and Applications, Volume 25 Author(s): Zhong-Jian Yang, Qian Zhao, Si Xiao, Jun He We study the optimization of near field enhancement in the two-wire optical antenna system. By varying the nanowire sizes we obtain the optimized side-length (width and height) for the maximum field enhancement with a given gap size. The optimized side-length applies to a broadband range (

Terahertz emission and photoluminescence of silicon nanowires electrolessly etched on the surface of silicon (100), (110), and (111) substrates for photovoltaic cell applications
Publication date: May 2017
Source:Photonics and Nanostructures - Fundamentals and Applications, Volume 24 Author(s): P. Tingzon, L. Lopez, N. Oliver, N. Cabello, A. Cafe, A. De Los Reyes, J. Muldera, E. Prieto, C. Que, G. Santos, M. Tani, A. Salvador, E. Estacio, A. Somintac Silicon nanowires (SiNWs) were etched on Si (100), (110), and (111) substrates. Slanted nanowires with respect to the surface normal were produced on the Si (110) and (111) substrates, and vertical nanowires were produced on the Si (100) substrate. Photoluminescence spectroscopy exhibited luminescence lines attributed to oxide defects from the nanowires. A comparison of the transient photocurrent as measured using terahertz time-domain spectroscopy revealed an increase in the THz emission from the SiNWs on Si (110) substrate compared to those grown on (100) substrate. Reorienting the dipole moment by applying an external 650mT magnetic field suggested that the carrier transport was confined along the axis of the nanowires. Understanding the photocarrier and transport recombination properties in SiNWs may prove useful in the design considerations for future SiNW photovoltaic cell applications.
view: 164

Bahamian Experiences at Atlantis -Rates from \$209 per night + up to \$300 in Resort Credit. Must book by 11/13!

Start: 08 May 2017 | End: 09 Feb 2018

(US) Garage Studio - Join the Loyalty Program and Receive 30% off 1 Regular Price Item on Your Birthday!

Start: 18 Aug 2017 | End: 01 May 2018

Save Up to 40% Off Budget-Friendly Used Tires at BestUsedTires.com!

Start: 03 Oct 2017 | End: 30 Apr 2018

Search All Amazon* UK* DE* FR* JP* CA* CN* IT* ES* IN* BR* MX