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The complementary electrochromic device, where the optical transmittance changes upon the flow of cations back and forth between anodic and cathodic electrodes, operates in a rocking‐chair fashion if it can inherently self‐discharge. Herein, the first demonstration of a dual‐mode electrochromic platform having self‐coloring and self‐bleaching characteristics is reported, which is realized by sandwiching zinc metal within a newly‐designed Prussian blue (PB)‐WO3 rocking‐chair type electrochromic device. It is demonstrated that the redox potential differences between the zinc metal and the WO3/PB electrodes endow the self‐color‐switching of these electrodes. By employing a hybrid electrolyte of Zn2+/K+, it is further shown that the colored PB‐WO3 rocking‐chair device is capable of spontaneously bleaching when the anodic and cathodic electrodes are coupled. This dual‐mode light‐control strategy enables the electrochromic devices to exhibit four distinct optical states with the highest optical contrast of 72.6% and fast switching times (<5 s for the bleaching/coloration processes). Furthermore, the built‐in voltage of the dual‐mode electrochromic devices not only promotes energy efficiency, but also augments the bistability of the devices. It is envisioned that the broad implication of the present platform is in the development of self‐powered smart windows, colorful displays, optoelectronic switches, and optical sensors. [ABSTRACT FROM AUTHOR]

Continued development in the areas of communication, security, medicine, and safety is calling for terahertz-wave technologies to evolve beyond laboratory research and into the realm of real-world applications. Due to the compatibility of waveguides with on-chip fabrication techniques and their ability to realize a small footprint, such structures provide a unique opportunity to achieve terahertz radiation generation in an on-chip arrangement, ideal for practical applications requiring terahertz electric fields. This review considers waveguiding arrangements that produce terahertz radiation using the nonlinear frequency-conversion techniques of optical rectification and difference frequency generation. The investigated terahertz radiation waveguiding sources are categorized into three different classes: those that confine and guide both the excitation electric fields and the generated terahertz radiation, those that confine and guide the excitation electric fields but not the generated terahertz radiation, and those that confine and guide the generated terahertz radiation but not the excitation electric fields. Various types of waveguides are surveyed from each category, including dielectric waveguides, metallic waveguides, photonic crystal waveguides, poled waveguides, and multiple waveguides embedded within one another. This review provides a detailed overview of state-of-the-art terahertz radiation waveguide sources, with the intent of aiding in the continuing development of such sources. [ABSTRACT FROM AUTHOR]

Continuous-wave terahertz (THz) radiation spectroscopy was performed on high explosive materials using a tuneable optical parametric oscillator (OPO). Military grade, solid-phase, explosive substances, such as cyclotetramethylenetetranitramine (HMX), cyclotrimethylenetrinitramine (RDX), pentaerythritol tetranitrate (PETN), and composition-4, were spectrally scanned over the 0.7-1.9 THz frequency range under experimental conditions modeling that of "real-world" security screenings. Spectral peak locations and spectral line broadening effects were quantified using a Lorentz lineshape fit algorithm. The full-width half-maximum (FWHM) parameter computed by the Lorentz fit algorithm was shown to help in the identification of samples with broad and sparse spectral characteristics. A concealed explosives identification scheme was demonstrated through raster scan THz frequency radiation imaging at specific OPO tuning frequencies. [ABSTRACT FROM AUTHOR]

Background: Femtosecond (fs) laser pulses have recently received wide interest as an alternative tool for manipulating living biological systems. In various model organisms the excision of cellular components and the intracellular delivery of foreign exogenous materials have been reported. However, the effect of the applied fs laser pulses on cell viability and development has yet to be determined. Using the zebrafish (Danio rerio) as our animal model system, we address both the short- and long-term developmental changes following laser surgery on zebrafish embryonic cells. Results: An exogenous fluorescent probe, fluorescein isothiocyanate (FITC), was successfully introduced into blastomere cells and found to diffuse throughout all developing cells. Using the reported manipulation tool, we addressed whether the applied fs laser pulses induced any shortor long-term developmental effects in embryos reared to 2 and 7 days post-fertilization (dpf). Using light microscopy and scanning electron microscopy we compared key developmental features of laser-manipulated and control samples, including the olfactory pit, dorsal, ventral and pectoral fins, notochord, pectoral fin buds, otic capsule, otic vesicle, neuromast patterning, and kinocilia of the olfactory pit rim and cristae of the lateral wall of the ear. Conclusion: In our study, no significant differences in hatching rates and developmental morphologies were observed in laser-manipulated samples relative to controls. This tool represents an effective non-destructive technique for potential medical and biological applications. [ABSTRACT FROM AUTHOR]

Focuses on the development of magnetooptic deflector based on thin-film iron garnet materials. Dynamics of magnetization; Polarization selectivity of deflected beam; Induction of high-frequency ferromagnetic resonance response of bismuth-substituted garnet.

Electrochromic devices with a wide color gamut distribution have long been sought after for non‐emissive display technologies. The current state‐of‐the‐art multicolor electrochromic displays utilize a single electrochromic layer, which restricts their color tunability within a linear or curved segment scope in International Commission on Illumination (CIE) color space and thus leads to limited color hues. Herein, it is demonstrated vivid electrochromic displays with broadened color hues via fabricating Zn‐based multicolor electrochromic displays having 2D CIE color space tunability. In addition, it is revealed that a Fabry–Perot nanocavity structure can further tune the color hues via altering the coordinate of the 2D CIE color space. It is known that this is the first demonstration of 2D CIE color space tunability realization from a single transparent or reflective electrochromic device. These findings represent a novel strategy for fabricating multicolor electrochromic displays and are expected to advance the development of electrochromic displays. [ABSTRACT FROM AUTHOR]

Since the discovery of electrochemical coloration phenomenon, electrochromic devices capable of monitoring transmittance, reflectance, and absorption at designated wavelengths have embraced great achievements. The marriage of electrochemistry and optical modulation has infused fascinating properties in electrochromic devices, which find applications in thermal management, display, smart windows, and camouflage. Inspired by the multipronged advancements in electrochemical devices, the incorporation of multivalent metal ions having rich electrochemistry into electrochromic devices is bloomed in recent years. Zinc, distinguished by its high crustal abundance, suitable standard redox potential, and inherent safety, has facilitated the assembly of highly efficient electrochromic devices. Zinc anode-based electrochromic devices with dual-band (visible and near-infrared) tunability, energy retrieval functions, multi-color options, multiple working modes (transmittance mode and reflectance mode), and scalability have been prominently showcased. Here in this review, the birth of zinc anode-based electrochromic devices will be systematically narrated, starting from the discovery of electrochromic phenomenon, to the evolution of electrochromic devices, and to the latest achievements in zinc anode-based electrochromic devices. Additionally, this review delves into the future development trends and perspectives of zinc anode-based electrochromic devices. This review serves as a handbook, which summarizes the history of electrochromism, introduces the physics behind it, highlights the development in zinc anode-based electrochromic devices, and aims to inspire future endeavors into this field, particularly those focused on developing energy-efficient electrochromic devices. [ABSTRACT FROM AUTHOR]

Highlights: La3+/Na+ bimetallically doped vanadate, designed for the first time, is promising in many electrochemical applications (e.g., batteries, electrochromics). This is the first report of electrochromic displays employing bimetallically doped vanadate. It is demonstrated for the first time that zinc dendrites and vanadate dissolution are significantly inhibited by employing an aqueous hybrid Zn2+/Na+ electrolyte. Vanadates are a class of the most promising electrochromic materials for displays as their multicolor characteristics. However, the slow switching times and vanadate dissolution issues of recently reported vanadates significantly hinder their diverse practical applications. Herein, novel strategies are developed to design electrochemically stable vanadates having rapid switching times. We show that the interlayer spacing is greatly broadened by introducing sodium and lanthanum ions into V3O8 interlayers, which facilitates the transportation of cations and enhances the electrochemical kinetics. In addition, a hybrid Zn2+/Na+ electrolyte is designed to inhibit vanadate dissolution while significantly accelerating electrochemical kinetics. As a result, our electrochromic displays yield the most rapid switching times in comparison with any reported Zn-vanadate electrochromic displays. It is envisioned that stable vanadate-based electrochromic displays having video speed switching are appearing on the near horizon. [ABSTRACT FROM AUTHOR]

Vanadium oxides are highly valued as electrochromic materials because of their multicolor capabilities. However, their practical applications have been limited due to challenges such as the dissolution of vanadate into aqueous electrolytes, leading to poor long‐term stability. Herein, a solution is proposed to the vanadate dissolution issue by utilizing a hybrid electrolyte consisting of tetraethylene glycol dimethyl ether (TEGDME) and water. This electrolyte has the unique ability to form a robust cathode electrolyte interface layer on vanadium oxide electrodes. As a proof of concept, zinc‐anode‐based multicolor transparent electrochromic displays are prepared using layered potassium vanadate (K2V6O16·1.5H2O, KVO) with a TEGDME–water hybrid electrolyte. By soaking the KVO electrode in the hybrid electrolyte, it is demonstrated that KVO has remarkable stability against dissolution. Furthermore, it is shown that KVO has superior electrochromic performance compared to sodium vanadate (NaV3O8·1.5H2O, SVO), due to the wide KVO interlayer spacing. Given the enhanced performance of this hybrid electrolyte and KVO cathode material, a zinc‐anode‐based electrochromic display prototype is shown to exhibit compelling performance. As such, this work is expected to be a significant catalyst for accelerating the development of vanadate‐based electrochromic displays. [ABSTRACT FROM AUTHOR]

The Zn anode-based electrochromic energy storage devices (EESDs) provide a promising strategy to overcome the contradiction of electrochromism and energy storage for efficient devices. In this regard, the device configuration can endow the electrochromic devices with superior electrochromic performance and excellent energy recovery efficiencies. [Display omitted] With the emerging demand of multifunctional optoelectronic devices, the integration of electrochromism and energy storage functionalities within a single platform has become a research frontier in the electrochromic community. However, the conventional electrochromic function is inherently contradictory to the energy storage function in electrochromic devices. In this review, we firstly introduced the working principles and device configurations of the rudimentary electrochromic energy storage devices (EESDs), where the origin of the contradiction between electrochromic and energy storage functionalities is comprehensively introduced. We then reviewed the current status and applications of EESDs, where we hope to clearly reveal the developing trends of the EESDs. Finally, we proposed our perspectives on the design strategy of zinc anode-based electrochromic devices for overcoming the contradiction between electrochromism and energy storage of EESDs. [ABSTRACT FROM AUTHOR]

The development of electrochromic materials has opened the door to the development of numerous devices including smart windows, color displays, optical filters, wearable camouflages, among others. Although the current electrochromic devices do not consume energy while maintaining their colored or colorless states, their bistable operation requires external electrical energy to be consumed during switching. To reduce the energy consumption of an electrochromic device, an emerging Zn anode‐based electrochromic device concept was recently introduced to partially retrieve the consumed electrical energy. In this Review, key technological developments and scientific challenges are presented for a broad range of Zn anode‐based electrochromic device configurations with emphasis on the inherent distinctions between the Zn anode‐based and conventional electrochromic devices. Specifically, a comprehensive comparison of the two classes of electrochromic devices in the high‐performance device design is provided. For the electrochromic layer, the methods for obtaining high‐quality electrochromic materials and thin films are reviewed. For the electrolytes, the effect of the dual ion system on the electrochromic performance is discussed. Also, some critical but unresolved issues in the device design and fabrication are discussed. The perspectives and outlook at the end of this Review provide recommendations to improve performance for future electrochromic studies. [ABSTRACT FROM AUTHOR]

Textile electronics embedded in clothing represent an exciting new frontier for modern healthcare and communication systems. Fundamental to the development of these textile electronics is the development of the fibers forming the cloths into electronic devices. An electronic fiber must undergo diverse scrutiny for its selection for a multifunctional textile, viz., from the material selection to the device architecture, from the wearability to mechanical stresses, and from the environmental compatibility to the end‐use management. Herein, the performance requirements of fiber‐shaped electronics are reviewed considering the characteristics of single electronic fibers and their assemblies in smart clothing. Broadly, this article includes i) processing strategies of electronic fibers with required properties from precursor to material, ii) the state‐of‐art of current fiber‐shaped electronics emphasizing light‐emitting devices, solar cells, sensors, nanogenerators, supercapacitors storage, and chromatic devices, iii) mechanisms involved in the operation of the above devices, iv) limitations of the current materials and device manufacturing techniques to achieve the target performance, and v) the knowledge gap that must be minimized prior to their deployment. Lessons learned from this review with regard to the challenges and prospects for developing fiber‐shaped electronic components are presented as directions for future research on wearable electronics. [ABSTRACT FROM AUTHOR]

Age-related macular degeneration (AMD) is a condition affecting the retina and is the leading cause of vision loss. Dry AMD is caused by the accumulation of lipid deposits called drusen, which form under the retina. This work demonstrates, for the first time, the removal of drusen-like deposits underneath ARPE-19 cell layers using femtosecond laser pulses. A novel cell culture model was created in response to the limited access to primary cell lines and the absence of animal models that recapitulate all aspects of AMD. In the cell culture model, deposits were identified with fluorescent stains specific to known deposit constituents. Trains of sub-10 femtosecond laser pulses from a Ti:Sapphire laser were used to successfully ablate the deposits without causing damage to surrounding cells. This drusen removal method can be used as a potential treatment for dry-stage AMD. [ABSTRACT FROM AUTHOR]

Electrochromic displays have attracted increased attention owing to their reversible switch of multicolors. However, the external voltage requirement for triggering the color switching makes them far from an optimum energy‐efficient technology. The newly developed electrochromic batteries eliminate the energy consumption for coloration while they can retrieve the consumed energy for bleaching. Such features make the electrochromic battery technology the most promising technology for energy‐efficient electrochromic displays. Here, a scalable method to synthesize colloidal V3O7 nanoparticles is presented, which is compatible with solution‐process techniques for aqueous Zn‐V3O7 electrochromic battery displays. The Zn‐V3O7 electrochromic battery display shows an optical transmittance contrast (21%), rapid self‐coloration time (6.6 s), and switching times (10.4/28.6 s for coloration/bleaching processes). Moreover, the electrochromic battery display shows a compelling energy retrieval function. For a proof of concept, a prototype display is constructed, which possesses an open‐circuit potential (OCP) of 1.38 V. The prototype display can reversibly switch between the multicolors (fully yellow, fully grayish‐blue, and half yellow‐half grayish‐blue images) and partially retrieve the consumed energy. This research presents a facile strategy to synthesize colloidal V3O7 nanoparticles, as well as a novel electrochromic battery display having energy retrieval functions, thus facilitating the development of energy‐efficient electrochromic displays. [ABSTRACT FROM AUTHOR]