Light Storage Research Articles

One pot synthesis of tungsten oxide nanomaterial and application in the field of flexible symmetric supercapacitor energy storage device

At present, electronic markets aim to develop new energy storage devices which are lightweight, portable, and flexible. In the present study, a flexible as well as a light weight energy storage device has been fabricated using tungsten oxide material. By a simple and effective hydrothermal technique, highly crystalline monoclinic tungsten oxide nanomaterial has been synthesised and the electrochemical performance of this material for supercapacitor energy storage application were analysed. Structural, optical and morphological studies were conducted using X-ray diffraction technique, Raman spectroscopy, Fourier transform infrared spectroscopy, and FESEM analysis. The electrochemical performance studies are carried out in two electrode set up. The supercapacitor device exhibits a specific capacitance of 64 F g -1 at 5 mV s−1.

Recycling of saw dust as a filler reinforced cotton seed oil resin amalgamated polystyrene composite material for sustainable waste management applications

Recently streamlining wood waste production and promote their recovery and recycling have been popularized with the sustainable utilization of the waste generated in the saw mill to promote sound, sustainable and healthy wood waste management practices. Herein, we report the development of polymer composite from the saw dust as a reinforced filler on the natural non-edible cotton seed oil resin as feedstock amalgamated with the styrene monomer. The prepared virgin polymer saw dust (VPSD) composite holds light weight, low cost, easy handling and storage, enhanced mechanical strength, low energy production, eco-friendliness, renewability and sustainable waste management. The reinforced polymer composite material was characterized by spectroscopic and microscopic techniques. The thermal studies of the as-prepared composite shows the extended thermal degradation due to the blending of saw dust into the polymeric process and its mechanical study confirms the enhanced stiffness due to the wooden dust. Due to the significant property obtained by reinforcing the saw dust in the natural resin matrix, the process could be used to extend the development of many polymeric feedstocks as a part of sustainable waste management process.

Three-band plasmon induced transparency effect based on four-disk resonator coupled waveguide system

In order to reduce power consumption and realize ultrafast response time and dynamic tunability, a plasmonic waveguide system based on four disk resonators is designed. A plasmon induced transparency effect is theoretically analyzed by using two different methods: one is the direct destructive interference between bright mode resonator and dark mode resonator, and the other is the indirect coupling through a plasmonic waveguide. Owing to the giant effective nonlinear Kerr coefficient of the graphene-Ag composite material structure and the enhancement characteristics of slow light response to optical Kerr effect, the pump intensity of PIT system for changing the phase shift of transmission spectrum is greatly reduced. An ultrafast response time of 1 ps is achieved, and 0.4π, 0.8π, 1.2π, 1.6π and 2π-phase shift of the transmission spectrum in the plasmon induced transparency system are achieved with the intensity of the pump light as low as 2.34, 4.68, 7.02, 9.36, 11.7 MW/cm<sup>–2</sup>, respectively. In this work, a plasmonic waveguide coupled directly by two small disk resonators is employed, because two small disk resonators play a role of the slit between the waveguide and the resonators, and also act as two separate resonators side-coupled with a plasmonic waveguide, which leads to the more efficient coupling of electromagnetic energy in the waveguide into the big disk resonators to form resonance and easier storage of light in the resonator. The triple-band plasmon induced transparency (PIT) effect and slow light properties of the model are analyzed by the expression of the deduced theoretical transmittance based on the coupled mode theory, indicating that they are very consistent with the finite-difference time-domain simulations. The results show that the transmission peak of the system is over 80% and the maximum group index is as high as 368. Furthermore, the disk resonators are easy to fabricate and the size of the entire PIT structure is < 0.5 μm<sup>2</sup>, which is beneficial to the design of optoelectronic device on-chip integration. The research results have important application prospects in highly integrating optical circuits and networks, and also provide the ideas for the design and fabrication of multi-channel optical filter and light storage devices with low power consumption, ultrafast nonlinear response, ultracompact and dynamical tunability.

Plasmon induced transparency effect based on graphene nanoribbon waveguide side-coupled with rectangle cavities system

In order to reduce the size of the device and realize the ultrafast response time and dynamic tunableness, the single-band and dual-band plasmon induced transparency (PIT) effect are investigated based on graphene nanoribbon waveguide side-coupled rectangle cavity. The slow light properties of the model are analyzed numerically and theoretically by coupled mode theory and finite difference time domain method. With controlling the chemical potential of the graphene rectangle cavity, the tunability of the resonant wavelength and the transmission peak can be achieved simultaneously in single-band and dual-band PIT model. As the chemical potential of graphene increases, the resonant wavelength of each transmission window of PIT effect decreases gradually and presents the blue shift. In addition, through dynamically tuning the resonant wavelength of the graphene rectangle cavity, when the chemical potential of the graphene rectangle cavity increases from 0.41 to 0.44 eV, the group index of single PIT system is controlled to be between 79.2 and 28.3, and the tunable bandwidth is 477 nm. Moreover, the group index of dual PIT system is controlled to be between 143.2 and 108.6 when the chemical potentials of graphene rectangle cavities 1, 2, and 3 are 0.39–0.42 eV, 0.40–0.43 eV, and 0.41–0.44 eV, respectively. The size of the entire PIT structure is <0.5 μm<sup>2</sup>. The research results here in this work are of reference significance in designing and fabricating the optical sensors, optical filters, slow light and light storage devices with ultrafast, ultracompact and dynamic tunableness.

Light Weight Cryptography based Medical Data and Image Encryption Scheme

Many medical companies use cloud technology to collect, distribute and transmit medical records. Given the need for medical information, confidentiality is a key issue. In this study, we propose an encrypted scheme based on encrypted data for an electronic healthcare environment. We use hybrid Attribute based encryption and Triple DES encryption technique (ABETDES) scheme, including identity-based cryptography (IBC), to ensure data privacy through communication channels և to improve the reliability of cloud computing. There are also limited indicators of light processing and storage resources. This solves a serious maintenance problem and ensures that a private key is created where it is not blind. The introduction of a security option, a comprehensive security analysis to protect ciphertext, shows that our program is effective against many known attacks and compared to existing methods.

Electromagnetically induced grating via Kerr nonlinearity and spontaneously generated coherence in a Doppler broadened four-level N-type atomic system

We study the electromagnetically induced grating in a four-level N-type atomic system in the presence of Kerr field, spontaneously generated coherence (SGC), and Doppler broadening. The transmission and diffraction intensity of the probe light is controlled through the Kerr field and the SGC. The gradual increase of the Kerr field and the SGC in the presence of a Doppler broadened medium leads to the enhanced multiple transmission and intensity peaks of the probe light. The electromagnetically induced grating may find applications in a quantized probe field, all-optical switching, routing, and light storage devices.

Photochemical Energy Conversion with Artificial Molecular Machines.

The exploitation of sunlight as a clean, renewable, and distributed energy source is key to facing the energetic demand of modern society in a sustainable and affordable fashion. In the past few decades, chemists have learned to make molecular machines, that is, synthetic chemical systems in which energy inputs cause controlled movements of molecular components that could be used to perform a task. A variety of artificial molecular machines operated by light have been constructed by implementing photochemical processes within appropriately designed (supra)molecular assemblies. These studies could open up new routes for the realization of nanostructured devices and materials capable to harness, convert, and store light energy.

Ensuring radiation safety during temporary storage of solidified radioactive waste in light hangar-type facilities

Expensive permanent storage facilities with massive engineered structures are used traditionally to ensure safe temporary storage of solidified radioactive waste at the NPP sites. Such approach is dictated by the need to comply with the regulatory requirements for limiting the gamma background in the area adjacent to the storage facility. The costs involved in temporary storage of solidified RW can be optimized by using light hangar-type storage facilities. At the same time, the safety of storage, including radiation protection of the personnel, the public and the environment, is undoubtedly ensured through the use of special organizational and engineering solutions. The Novovoronezh NPP, a branch of JSC Concern Rosenergoatom, operates successfully light hangar-type facilities for temporary storage of solidified RW classified as medium-level waste in accordance with OSPORB-99/2009. In the process of operation, a methodology and a method for conditioning and temporary storage of solidified RW were developed to ensure the RW removal for final disposal with no extra process operations and unreasonable costs. A methodology has been developed to assess the radiation situation around storage facilities during temporary storage of RW, as well as a software package for predicting the radiation situation when deciding on the arrangement of the storage facility’s peripheral rows.

Long‐Range Charge Transportation Induced Organic Host–Guest Dual Color Long Persistent Luminescence

AbstractLong persistent luminescence (LPL) can store light energy in excited states and gradually release it as light. Organic host–guest systems provide a good platform for LPL, and single‐color LPL is often achieved while multicolor LPL is challengeable. Here host–guest supramolecular complexes are presented with dual LPL emissions: thermally activated delayed fluorescence (TADF) (≥100 ms) and room temperature phosphorescence (RTP). A space charge transfer from α‐cyclodextrin to diphenylacetylene (DPA) with long‐range transportation (2.32 mm) carrier along DPA strand in the supramolecular complexes is attributed to generate the TADF and RTP. Fortunately, these supramolecular complexes are readily fabricated from α‐cyclodextrin and DPA or DPA derivatives. The gradient color is observed after removing UV excitation. Furthermore, the hydrophobic property inside α‐cyclodextrin makes the LPL appear by water shedding and disappear by organic solvent infiltration, showing the character of a “switch.” This host–guest space charge transfer strategy paves a way to design LPL materials.

Tackling the ‘death’ of brick-and-mortar clothing retailers through store atmospherics and customer experience

The threat of online shopping propels brick-and-mortar retailers to innovate and design their retail atmosphere to create unforgettable shopping experiences to compete effectively and retain customers. The study firstly identifies store atmospherics factors that enhance the shopping experience and secondly explores the hypothesized relationships between store atmospherics dimensions (lighting, music, layout, and employee interaction) and customer experience. Furthermore, the effect of customer experience and repurchase intention is also explored. A self-administered survey was used, and data were collected from 390 respondents who visit physical clothing stores regularly in the City of Johannesburg in South Africa. The survey results were analyzed using the Statistical Package for Social Sciences (SPSS) for descriptive statistics. Covariance-Based Structural Equation Modelling (CB-SEM) was utilized for the path analysis. The findings reveal that only store layout, lighting, and employee interaction are essential elements in creating pleasurable customer in-store experiences (β = 0.163, p = 0.05; β = 0.207, p = 0.01; β = 0.293, p = 0.001). It is also evident that consumers perceive music to be less effective in enhancing their shopping experiences (β = 0.048, p = ns). Moreover, the results show that enriching customer experiences stimulate repeat purchases (β = 0.745, p = 0.001). The findings demonstrate that innovating the store environment should be based on shop layout, illumination, and employee contact to create appealing experiences. This study contributes to consumer and retailing services literature. Acknowledgment This study is based on the research supported partly by the University of the Witwatersrand Chancellor’s Female Academic Leaders Fellowship.

Experimental investigation of light storage of diffraction-free and quasi-diffraction-free beams in hot atomic gas cell

Experimental investigation of light storage of diffraction-free and quasi-diffraction-free beams in hot atomic gas cell

Comparison of AC and DC Nanogrid for Office Buildings with EV Charging, PV and Battery Storage

Future office buildings are expected to be integrated with energy intensive, inherently DC components such as photovoltaic panels (PV), electric vehicles (EV), LED lighting, and battery storage. This paper conceptualizes the interconnection of these components through a 750 V DC nanogrid as against a conventional three-phase 400 V AC system. The factors influencing the performance of a DC-based nanogrid are identified and a comparative analysis with respect to a conventional AC nanogrid is presented in terms of efficiency, stability, and protection. It is proved how the minimization of grid energy exchange through power management is a vital system design choice. Secondly, the trade-off between stability, protection, and cost for sizing of the DC buffer capacitors is explored. The transient system response to different fault conditions for both AC and DC nanogrid is investigated. Finally the differences between the two systems in terms of various safety aspects are highlighted.

Solution-Processed Photoinduced Multilevel Resistive Switching Devices Based on Lead-Free All-Inorganic Perovskite

The letter reports lead free all-inorganic perovskite based resistive switching (RS) memory devices. The cesium tin bromide (CsSnBr <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> ) perovskite films were prepared by the solution deposition technique. The memory devices exhibit bipolar resistive RS characteristic and light assisted multilevel storage capability. The proposed devices show a maximum ON/OFF ratio of ~ 10 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">5</sup> , data retention of ~ 10 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sup> s, and endurance of 400 cycles. We explain the resistive switching effect on lights of the formation and rupture of a conducting path under an electric field. This work may provide an opportunity to develop transparent, flexible, and multibit storage capacity photonic resistive memory devices based on all-inorganic perovskites for successful logic application.

The formation of phycocyanin-EGCG complex for improving the color protection stability exposing to light

Phycocyanin (PC) is a natural pigment-protein complex in food dye applications. In this study, a phycocyanin-epigallocatechin gallate (EGCG) complex (PE) was prepared and the effects of EGCG on the structure and color stability of PC were evaluated. The fluorescence results showed that the binding number n was 62.1 ± 3.41 (EGCG/PC) and the binding constant K was 4.39 (±0.2) × 105 M−1, indicating a weak-binding interaction. Fourier transform-infrared analysis showed that EGCG caused structural changes in PC by partially uncoiling α-helix and increasing β-sheet content. The EGCG induced a PC association at a reaction molar ratio above 40:1 (EGCG/PC). Moreover, EGCG protected phycocyanobilin against color fading, making PE more stable relative to PC under 8-days storage in light. This study provides a novel scheme to stabilize PC by forming a complex with polyphenols, which will facilitate the PC application as a natural blue pigment in food.

Single-photon-level light storage with distributed Rydberg excitations in cold atoms

Single-photon-level light storage with distributed Rydberg excitations in cold atoms

Efficient White Light Emission from Ga/Ga2O3 Hybrid Nanoparticles

AbstractGallium (Ga) emerges as a promising material in plasmonics mainly due to its extraordinary properties, such as changeable material phase, tunable plasmon resonances across the ultraviolet to near‐infrared spectral range, and remarkable chemical stability. Here, the efficient white light emission from gallium oxide (Ga2O3) nanoparticles doped with liquid Ga nanodots, which are fabricated by using a laser‐induced oxidation method is reported. The quantum efficiency of Ga/Ga2O3 hybrid nanoparticles is found to be ≈1.3%, which is nearly two orders of magnitude larger than that of liquid Ga nanoparticles. It is revealed that the existence of Schottky barrier and hotspots in Ga/Ga2O3 nanoparticles plays a crucial role in enhancing the quantum efficiency. As an example of practical applications, high‐quality optical data storage is demonstrated by exploiting the controllable formation of Ga/Ga2O3 nanoparticles on a platform of disordered Ga nanoislands. These results suggest the potential applications of Ga/Ga2O3 hybrid nanoparticles in the development of nanoscale light sources and data storage devices.

Dual quasibound states in the continuum in compound grating waveguide structures for large positive and negative Goos-Hänchen shifts with perfect reflection

Based on the selective excitations of the forward and backward propagating resonant guided modes, we achieve $dual$ bound states in the continuum ($dual$ BICs) in a compound grating waveguide structure composed of a four-part periodic grating layer and a waveguide layer. Assisted by the quasi-BIC corresponding to forward propagating resonant guided mode (quasi-BIC 1) and the one corresponding to backward propagating resonant guided mode (quasi-BIC 2), large $positive$ and $negative$ GH shifts can be simultaneously realized. Also, in contrast to the GH shift enhanced by conventional transmission-type resonance, large positive and negative GH shifts assisted by dual quasi-BICs possess 100% reflectance, which can be more easily detected and utilized. Our work provides a route to design GH-shift-based high-performance sensors, wavelength division (de)multiplexers and light storage devices.

In situ ac Stark shift detection in light storage spectroscopy

We report on a method for measuring ac Stark shifts observed in stored light experiments while simultaneously determining the energetic splitting between the electronic ground states involved in the two-photon transition. To this end, we make use of the frequency matching effect in light storage spectroscopy. We find a linear dependence on the intensity of the control field applied during the retrieval phase of the experiment. At the same time, we observe that the light shift is insensitive to the intensity of the signal field which is in contrast to continuously operated electromagnetically induced transparency (EIT) or coherent population trapping (CPT) experiments, where the light shifts induced by all participating optical fields have to be taken into account. Our results may be of importance for future precision measurements in addition to or in combination with current EIT and CPT-type devices which are largely compatible with our approach and could benefit from the inherent robustness regarding operational conditions, shape of the resonances or intensity fluctuations in the signal field.

Effects of Light Exposure, Bottle Colour and Storage Temperature on the Quality of Malvasia delle Lipari Sweet Wine.

The influence of light exposure, bottle color and storage temperature on the quality parameters of Malvasia delle Lipari (MdL) sweet wine were investigated. Wine samples bottled in clear-colored (colorless, green and amber) glass were stored under different artificial lighting conditions, in order to simulate the retail environment (one cool-white, fluorescent lamp) and to perform an accelerated test (four and six cool-white, fluorescent lamps). The storage temperature was kept constant (25 °C) for the first 90 days of the experiment and then samples were monitored for up to 180 days at higher temperatures (30, 35 and 40 °C). The principal enological parameters, total phenols, color, 5-hydroxymethylfurfural (HMF) and 2-furaldehyde (2F) contents were studied. The shelf-life test pointed out minimum variations of the basic chemical parameters, while the quality attributes most affected by lighting were color, together with HMF and 2F levels which, hence, can be considered as indicators of the severity of storage conditions.

“Spiral COSAMI” — A Multi-Undulator Compact Source for Actinic Mask Inspection in the extreme ultraviolet range

A compact electron storage ring provides a bright, stable and reliable source of extreme ultraviolet (EUV) radiation for metrology applications in semiconductor industry. The COSAMI concept (COmpact Synchrotron for Actinic Mass Inspection) applied design principles and technology of modern diffraction limited light source storage rings to an EUV facility operating at 13.5 nm wavelength. Since floor space is an important issue in an industrial environment, we propose a lattice configuration where three (or more) recirculation turns are stacked vertically. We present a facility, called Spiral-COSAMI, which simultaneously serves multiple (three or more) EUV beamlines within about the same floor space of the original COSAMI, and using the same type of injector and the same set of diagnostics, radio-frequency and pulsed magnet devices. The increased period of revolution of the multiple turns mitigates the problem of ion trapping and relaxes specifications of injection kickers.