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Two-terminal structure memristors are the most promising electronic devices that could play a significant role in artificial intelligence applications of the next generation and the post-Moore era. In this work, we fabricated the memristive device by depositing a heterojunction WOx/TiOy functional layer onto an indium tin oxide substrate using magnetron sputtering. The Ag/WOx/TiOy/ITO device exhibits improved memory behavior of bipolar resistive switching (RS) nonvolatile compared to TiOy-based single-layer memristors, enabling it to meet high-density information storage requirements. Moreover, our device exhibited the coexistence of the negative differential resistance effect and the behavior of the RS memory. Through a comprehensive analysis of conductivity on the curve of current–voltage (I–V), a physical model based on the mechanism of space charge-limited current, ohmic conduction, and Schottky emission was suggested to explain the behavior device RS memory. This study's findings demonstrate that including a heterojunction bilayer WOx/TiOy as a functional layer can significantly improve the performance of memristive devices. This advancement expands the potential application of ferroelectric metallic oxide heterojunctions within the field of memristors. [ABSTRACT FROM AUTHOR]

Plasmon-mechanical resonators are frequently employed in sensor development. Here, I report the coupling of plasmon and mechanical modes in a multilayer architecture. In the experiment, the multilayer comprised indium tin oxide (ITO) and silver (Ag) mirrors placed on the top and bottom of a SiO2 substrate. By activating a Fabry–Pérot hybrid mode and surface plasmon polariton in a Kretschmann configuration, I demonstrated the generation of a hybrid plasmon-mechanical mode by plasmonic dispersion and through strong coupling, which resulted in mechanical distortion at multiple frequencies. Adsorption of rhodamine G6 on Ag modifies the optomechanical spectrum; it causes eigenmodes to split, resulting in a coupling rate greater than the optical decay rate (κ ∗ < g). Besides, the excitonic modes were observed to interact with plasmon-mechanical modes, especially on-resonance, where the plasmon-mechanical modes exhibited the higher intensity. For example, the out-of-phase flexural mode (iii, g 0 = 427 × 2 π kHz) became active because of the coupling of the dye. Meanwhile, after dye absorption, the strong in-phase compressional mode (iv, g 0 = 560 × 2 π kHz) exhibited the widest splitting and an increase in the side peaks, which merged when the pump power was raised. The system was then analyzed to determine the ideal experimental settings for detecting mass by the oscillator in a controlled experiment. The mass sensor responsivity was evaluated to be F = 10 17 Hz g − 1 . Advantages and disadvantages of this approach are presented. [ABSTRACT FROM AUTHOR]

Information processing and memorizing in the brain take place in a neural network consisting of neurons connected with each other by synapses. Meanwhile, the neural network is immersed in a common electrochemical environment with global parameters regulating the overall functions, which is barely discussed in neuromorphic devices. In this study, organic/inorganic hybrid transistors with sodium alginate as the gate dielectric layer and indium tin oxide as the channel were successfully prepared. We have not only simulated the basic properties of synapses in a single device, but, on top of that, also simulated the global regulation of information processing in the brain due to the incorporation of global grids, achieving excitatory and inhibitory synaptic weight. Moreover, the construction of a 3 × 3 synaptic array enables image learning and memorizing functions. These results demonstrate the significant advantages of electrolyte-gated transistors in enabling complex neural network connectivity and offer a promising opportunity for future artificial synapses. [ABSTRACT FROM AUTHOR]

The use of flashlamp annealing as a low-temperature alternative or supplement to thermal annealing is investigated. Flashlamp annealing and thermal annealing were conducted on 100 nm thick indium tin oxide (ITO) films deposited on glass to compare the properties of films under different annealing methods. The ITO samples had an average initial sheet resistance of 50 Ω/sq. After flashlamp annealing, the sheet resistance was reduced to 33 Ω/sq only, while by thermal annealing at 210 °C for 30 min, a sheet resistance of 29 Ω/sq was achieved. Using a combination of flashlamp annealing and thermal annealing at 155 °C for 5 min, a sheet resistance of 29 Ω/sq was achieved. X-ray diffraction analysis confirmed that flashlamp annealing can be used to crystallize ITO. Flashlamp annealing allows for low-temperature crystallization of ITO on a time scale of 1–3 min. Through electrical and optical characterizations, it was determined that flashlamp annealing can achieve similar electrical and optical properties as thermal annealing. Flashlamp offers the method of low-temperature annealing, which is particularly suitable for temperature sensitive substrates. [ABSTRACT FROM AUTHOR]

Epitaxial Mn-doped indium tin oxide (ITO) films were deposited on single-crystal yttria stabilized zirconia (YSZ) substrates with (111), (110), and (100) crystal plane orientations using RF magnetron sputtering. The epitaxial relationship between the Mn-doped ITO films and the YSZ substrates was studied using x-ray diffraction (XRD) patterns in the ω–2θ scan mode and XRD pole figures. The Mn-doped ITO films on the YSZ(111) and YSZ(110) substrates exhibited a higher degree of crystallinity than the film on the YSZ(100) substrate as per the x-ray rocking curves. Fluctuations in the crystalline alignment were found to significantly influence the electrical properties of Mn-doped ITO films. Ferromagnetic hysteresis loops were observed at room temperature for all the epitaxial Mn-doped ITO films, irrespective of their crystallographic orientation. The magnetic properties of the epitaxial Mn-doped ITO films suggest that a combination of delocalized charge carrier-mediated interaction and bound magnetic polaron-driven interaction is required to explain the origin of ferromagnetism in these films. The Mn-doped ITO film on the YSZ(111) substrate exhibited the most desirable characteristics in terms of crystallinity, surface smoothness, electrical conductivity, and magnetic properties. [ABSTRACT FROM AUTHOR]

Indium tin oxide (ITO) film, which is the most commonly used transparent conductive film (TCF), has traditionally been believed to be transparent in the visible spectrum but to reflect infrared (IR) light beyond the plasma wavelength (λp). However, our theoretical analysis challenges this notion by demonstrating that an ultrathin ITO TCF that is thinner than the light's penetration depth can overcome the transmission barrier at λp. To validate the theoretical modeling, we have successfully fabricated ultrathin ITO films that, despite having λp ≈ 1 μm, remain transparent from 400 nm to 20 μm. This represents the broadest transparency range ever reported for any In2O3-based TCF. The 10-nm-thick ITO TCFs have high visible transmittance (91.0% at 550 nm), low resistivity (5 × 10−4 Ω cm), and good IR transmittance (averaging 60% over 1.35–18.35 μm). Their IR transparency facilitates radiative cooling of the underlying circuitry. When an operational resistor is enclosed by commercial ITO TCFs that are 140 nm thick, its temperature increases. However, using 10-nm-thick ITO TCFs instead of the commercial ones can completely avoid this temperature rise. Moreover, attaching a silver grid to a 10-nm-thick ITO TCF can reduce the effective sheet resistance to ∼10 Ω/□ at the expense of only ∼3% transmittance. This development paves the way for large-scale applications that require low sheet resistance and far-IR transparency. [ABSTRACT FROM AUTHOR]

Oxygen vacancies in indium tin oxide (ITO) thin films provide a direct route to effectively tune the free electron density and thereby, controlling the epsilon-near-zero (ENZ) cut-off wavelength, the wavelength at which the real part of permittivity crosses zero of the permittivity axis. In this report, oxygen vacancies in pulsed laser deposited ITO thin films are systematically tuned using different background gases (O 2 , N 2 , Ar, and He). ENZ cut-offs are observed for the films deposited under He and Ar gases. In contrast, no such cut-offs are observed in the case of other two gases. An ITO thin film deposited under He gas exhibits deeper resonance signal than the one deposited under Ar gas. As expected, no such dip in the resonance spectra is observed for the films deposited under O 2 and N 2 gases. This observation is directly correlated to the change in the number of oxygen vacancies under different ambient gases. A modified transfer matrix method which incorporates surface roughness as an effective medium layer is developed to describe the experimentally observed resonance spectra numerically. Angular invariancy of ENZ plasmon resonance and the difference in absorption values for ITO films deposited under different gases is understood in terms of local field intensity enhancement factor. The study presented here will certainly be very useful in understanding the ENZ plasmon resonance phenomena as a whole. Additionally, ITO films deposited under an inert gas environment could be excellent material platforms for realizing several exotic ENZ applications. [ABSTRACT FROM AUTHOR]

In this work, we investigated the effect of hole transporting poly(3,4-ethylenedioxythiophene):polystyrene sulfonate (PEDOT:PSS) interfacing with Mn-doped CdS/ZnS quantum dots (QDs) deposited on an indium tin oxide (ITO) substrate on the photoemission of upconverted hot electrons under weak continuous wave photoexcitation in a vacuum. Among the various factors that can influence the photoemission of the upconverted hot electrons, we studied the role of PEDOT:PSS in facilitating the hole transfer from QDs and altering the energy of photoemitted hot electrons. Compared to hot electrons emitted from QDs deposited directly on the ITO substrate, the addition of the PEDOT:PSS layer between the QD and ITO layers increased the energy of the photoemitted hot electrons. The increased energy of the photoemitted hot electrons is attributed in part to the reduced steady-state positive charge on the QDs under continuous photoexcitation, which reduces the energy required to eject the electron from the conduction band. [ABSTRACT FROM AUTHOR]

Bio-spinterfaces present numerous opportunities to study spintronics across the biomolecules attached to (ferro)magnetic electrodes. While it offers various exciting phenomena to investigate, it is simultaneously challenging to make stable bio-spinterfaces as biomolecules are sensitive to many factors that it encounters during thin-film growth to device fabrication. The chirality-induced spin-selectivity effect is an exciting discovery, demonstrating an understanding that a specific electron's spin (either up or down) passes through a chiral molecule. The present work utilizes Ustilago maydis Rvb2 protein, an ATP-dependent DNA helicase (also known as Reptin), to fabricate bio-spintronic devices to investigate spin-selective electron transport through the protein. Ferromagnetic materials are well-known for exhibiting spin-polarization, which many chiral and biomolecules can mimic. We report herein spin-selective electron transmission through Rvb2 that exhibits 30% spin polarization at a low bias (+0.5 V) in a device configuration, Ni/Rvb2 protein/indium tin oxide measured under two different magnetic configurations. Our findings demonstrate that biomolecules can be put in circuit components without any expensive vacuum deposition for the top contact. The present study holds a remarkable potential to advance spin-selective electron transport in other biomolecules, such as proteins and peptides, for biomedical applications. [ABSTRACT FROM AUTHOR]

Defects in pulsed-laser deposition grown $\kappa{\hbox -}{\rm Ga}_2{\rm O}_3$ have been investigated using thermal admittance spectroscopy and secondary ion mass spectrometry (SIMS). A $\kappa {\hbox -}{\rm Ga}_2{\rm O}_3$ film was grown on either a tin-doped indium oxide or an aluminum-doped zinc oxide buffer layer on a sapphire substrate functioning as back contact layer in vertical diode structures. In both sample types, a distinct signature in the capacitance signal was observed in the temperature range of 150–260 K. The corresponding defect charge-state transition level, labeled $E_0$ , was found to exhibit an activation energy of 0.21 eV. Potential candidates for the $E_{0}$ level were investigated using a combination of SIMS and hybrid-functional calculations. SIMS revealed the main impurities in the sample to be tin, silicon, and iron. The hybrid-functional calculations predict the acceptor levels of substitutional iron to lie 0.7–1.2 eV below the conduction band minimum depending on Ga-site, making ${\rm Fe}_{{\rm Ga}}$ an unlikely candidate for the $E_0$ level. Furthermore, Si as well as Sn substituting on the sixfold coordinated Ga2 site and the fivefold coordinated Ga3 and Ga4 sites are all shallow donors in $\kappa$ - ${\rm Ga}_2{\rm O}_3$ , similar to that of $\beta$ - ${\rm Ga}_2{\rm O}_3$. Sn substituting on the fourfold Ga1 site is, however, predicted to have levels in the bandgap at 0.15 and 0.24 eV below the conduction band minimum, in accordance with the extracted activation energy for $E_{0}$. Thus, we tentatively assign ${\rm Sn}_{{\rm Ga}1}$ as the origin of the $E_0$ level. [ABSTRACT FROM AUTHOR]

Indium tin oxide (ITO) ceramics with different SnO2 contents were fabricated using the conventional solid-state reaction. The phase structure, microstructure, electrical conductivity, heating, and mechanical properties were investigated in detail. The results showed that pure ITO ceramics with high relative density were obtained successfully. The ITO ceramics were cut into regular rectangles to serve as electrical heaters. Additionally, their saturation temperatures and thermal response times were tested at different voltages. The results showed that ITO ceramics with 10% SnO2 had the fastest thermal response rate and reached a saturation temperature of 376∘C at 1.5 V voltage, the highest temperature reported in the literature for In2O3 ceramics. Moreover, In2O3 with 10% SnO2 showed good mechanical properties. Hence, ITO ceramics, as electrical heaters with low driving voltage and high response speed, are expected to have potential heating applications such as domestic heating and industrial production. [ABSTRACT FROM AUTHOR]

In this paper, two D–π–A structured self-assembly monolayers (SAMs: FNE29 and DT-1) are self-assembled onto the indium tin oxide (ITO) substrates as hole-transport layers (HTLs) for inverted perovskite solar cells (PSCs). Due to the presence of a terminal –COOH group, the SAMs can be adsorbed onto the surface of the ITO substrate through the covalent self-assembly. The employed FNE29 and DT-1 SAMs differ in the π bridge (linker); the FNE29 SAM has a hexyl-substituent terthiophene while the DT-1 SAM contains dithienopyrrolobenzotriazole as the linkers, respectively. Upon the self-assembly of ITO with the SAMs, the power conversion efficiency (PCE) is enhanced from 9.36% for the control device to 16.75% for the FNE29 modified device and further to 20.65% for the DT-1 modified PSCs. As the D–π–A structured SAMs with a large fused π bridge as a linker is beneficial for hole transfer, the self-assembly of DT-1 achieves a higher PCE with an improved fill factor. Moreover, due to the good hydrophobic characteristics of the SAMs, the inverted PSC devices self-assembled with these two molecules display good stability, maintaining over 80% of the original PCE after storage in air (relative humidity of 20–30%) for ∼1000 h without encapsulation. In addition, the FNE29 and DT-1 based devices also show good photostability after operating for 1000 h. These results indicate that the D–π–A structured SAMs with large conjugated fused π bridges as linkers have obvious advantages as the HTLs for inverted PSCs. [ABSTRACT FROM AUTHOR]

Adherent bubbles at electrodes are generally treated as reaction penalties. Herein, in situ hydroxylation of indium tin oxide surfaces can be easily achieved by applying a constant potential of +1.0 V in the presence of bubbles. Its successful hydroxylation is further demonstrated by preparing a ferrocene-terminated film, which is confirmed by cyclic voltammetry and X-ray photoelectron spectroscopy. [ABSTRACT FROM AUTHOR]

Due to its excellent electrical conductivity, high transparency in the visible spectrum, and exceptional chemical stability, indium tin oxide (ITO) has become a crucial material in the fields of optoelectronics and nanotechnology. This article provides a thorough analysis of growing ITO thin films with various thicknesses to study the impact of thickness on their electrical, optical, and physical properties for solar-cell applications. ITO was prepared through radio frequency (RF) magnetron sputtering using argon gas with no alteration in temperature or changes in substrate heating, followed with annealing in a tube furnace under inert conditions. An investigation of the influence of thickness on the optical, electrical, and physical properties of the films was conducted. We found that the best thickness for ITO thin films was 100 nm in terms of optical, electrical, and physical properties. To gain full comprehension of the impact on electrical properties, the different samples were characterized using a four-point probe and, interestingly, we found a high conductivity in the range of 1.8–2 × 106 S/m, good resistivity that did not exceed 1–2 × 10−6 Ωm, and a sheet resistance lower than 16 Ω sq−1. The transparency values found using a spectrophotometer reached values beyond 85%, which indicates the high purity of the thin films. Atomic force microscopy indicated a smooth morphology with low roughness values for the films, indicating an adequate transitioning of the charges on the surface. Scanning electron microscopy was used to study the actual thicknesses and the morphology, through which we found no cracks or fractures, which implied excellent deposition and annealing. The X-ray diffraction microscopy results showed a high purity of the crystals, as the peaks (222), (400), (440), and (622) of the crystallographic plane reflections were dominant, which confirmed the existence of the faced-center cubic lattice of ITO. This work allowed us to design a method for producing excellent ITO thin films for solar-cell applications. [ABSTRACT FROM AUTHOR]

Phase‐change‐materials (PCMs) integrated photonics have attracted extensive attention in the field of optical neural networks. However, present PCMs‐integrated photonics are still far from meeting the requirements in real‐world applications due to its unsatisfactory endurance (<3000 cycles) and extinction ratio (ER<20 dB). Here, ultrahigh endurance (>30 000 cycles) and large ER (≥50 dB) are achieved in the photonic device by introducing a trench structure to the indium tin oxide (ITO) heater and utilizing tin‐doped Ge2Sb2Te5 (Sn‐GST) as PCMs. This performance represents a landmark in the PCMs‐integrated photonics, since it solves the problem of poor endurance of ITO heaters and can be comparable to the state‐of the‐art devices in terms of endurance and ER. This excellent endurance and ER stem from the trench structure and high optical contrast PCM of Sn‐GST. Trench structure improves the heating efficiency of the ITO heater and effectively alleviates the thermal stress imposed on the ITO heater, resulting in ultrahigh endurance of the device. Sn‐doping is also beneficial to the endurance and ER improvement, because it can effectively reduce the crystallization temperature and increase the absorption coefficient of the PCM layer. This work provides a new technology for the development of programmable photonics with ultrahigh endurance. [ABSTRACT FROM AUTHOR]

Despite the perovskite solar cells (PSCs) have attracted attention due to their high efficiency and lower cost compared to Si solar cells, many issues remain to be addressed for the commercialization. While the perovskite light absorbing materials is relatively inexpensive, the charge transport layers such as the hole transport layer (HTL) or electron transport layer (ETL) are usually composed of expensive organic compounds. In that sense, PSCs without the charge transport layers are developed, showing very low performance due to low charge collection efficiency. In this study, we investigate the origin of low efficiency for ETL or HTL-free PSCs, and further identify the suitable front contact (either indium tin oxide (ITO) or fluorine-doped tin oxide (FTO)) for each PSC by using numerical simulation and experimental validation. The different work functions of the front contacts significantly influence charge extraction behavior, thereby affect the charge transport layer free devices. [ABSTRACT FROM AUTHOR]

Flexible electronic devices have promising applications in many future technologies such as wearables, implantables, robotics, and displays. Among the distinct types of mechanical flexibility, stretchability stands as a significant challenge. A particularly demanding objective is the realization of a high‐performance transparent electrode that endures stretching and can be mass produced, all while avoiding additional restrictions on device density. In this work, it is demonstrated that a 3D wave patterned surface provides a threefold improved strain performance of deposited indium tin oxide electrodes, in a statistical comparison of 3D wave patterned and planar surfaces, where indium tin oxide electrodes are stretched to electrical failure. Moreover, this platform alleviates residual thin film stress, allowing for easier handling of the substrates. This study demonstrates the feasibility of attaining stretchability for upcoming electronic devices using a scalable platform that incorporates high‐performance transparent electrode materials using only conventional materials and fabrication steps. [ABSTRACT FROM AUTHOR]

Power conversion efficiencies (PCEs) of inverted perovskite solar cells (PSCs) have been improved by the use of a self-assembled monolayer (SAM) hole transport layer. Long-term stability of PSCs requires keeping the SAM compact under the perovskite layer during operation. We found that strong polar solvents in the perovskite precursor desorb the SAM if it is anchored on substrates by hydrogen-bonded, rather than covalently bonded, hydroxyl groups. We used atomic-layer deposition to create an indium tin oxide substrate with a fully covalent hydroxyl-covered surface for SAM anchoring, as well as a SAM with a trimethoxysilane group that exhibited strong tridentate anchoring to the substrate. The resulting PSCs achieved PCEs of 24.8 (certified 24.6) and 23.2% with aperture areas of 0.08 and 1.01 square centimeters, respectively. The devices retained 98.9 and 98.2% of the initial PCE after 1000 hours damp-heat test and operation in maximum power point tracking at 85°C for 1200 hours under standard illumination, respectively. [ABSTRACT FROM AUTHOR]

[Display omitted] Thin-film sensors are essential for real-time monitoring of components in high-temperature environments. Traditional fabrication methods often involve complicated fabrication steps or require prolonged high-temperature annealing, limiting their practical applicability. Here, we present an approach using direct ink writing and laser scanning (DIW-LS) to fabricate high-temperature functional thin films. An indium tin oxide (ITO)/preceramic polymer (PP) ink suitable for DIW was developed. Under LS, the ITO/PP thin film shrank in volume. Meanwhile, the rapid pyrolysis of PP into amorphous precursor-derived ceramic (PDC) facilitated the faster sintering of ITO nanoparticles and improved the densification of the thin film. This process realized the formation of a conductive network of interconnected ITO nanoparticles. The results show that the ITO/PDC thin film exhibits excellent stability, with a drift rate of 4.7 % at 1000 °C for 25 h, and withstands temperatures up to 1250 °C in the ambient atmosphere. It is also sensitive to strain, with a maximum gauge factor of −6.0. As a proof of concept, we have used DIW-LS technology to fabricate a thin-film heat flux sensor on the surface of the turbine blade, capable of measuring heat flux densities over 1 MW/m2. This DIW-LS process provides a viable approach for the integrated, rapid, and flexible fabrication of thin film sensors for harsh environments. [ABSTRACT FROM AUTHOR]

Advanced flexible ionotronic devices have found excellent applications in the next generation of electronic skin (e-skin) development for smart wearables, robotics, and prosthesis. In this work, we developed transparent ionotronic-based flexible electrochemical capacitors using gel electrolytes and indium tin oxide (ITO) based transparent flexible electrodes. Different gel electrolytes were prepared using various salts, including NaCl, KCl, and LiCl in a 1:1 ratio with a polyvinyl alcohol (PVA) solution and compared its electrochemical performances. The interaction between gel electrolytes and ITO electrodes was investigated through the development of transparent electrochemical capacitors (TEC). The stable and consistent supply of ions was provided by the gel, which is essential for the charge storage and discharge within the TEC. The total charge contribution of the developed TECs is found from the diffusion-controlled mechanism and is measured to be 4.59 mC cm−2 for a LiCl/PVA-based gel. The prepared TEC with LiCl/PVA gel electrolyte exhibited a specific capacitance of 6.61 mF cm−2 at 10 μA cm−2. The prepared electrolyte shows a transparency of 99% at 550 nm and the fabricated TEC using LiCl/PVA gel exhibited a direct bandgap of 5.34 eV. The primary benefits of such ionotronic-based TEC development point to its potential future applications in the manufacturing of transparent batteries, electrochromic energy storage devices, ionotronic-based sensors, and photoelectrochemical energy storage devices. [ABSTRACT FROM AUTHOR]

Ultra-thin flexible glass with thicknesses of 100 μm or below is a substrate in the fields of optics, electronics, and semiconductors. Its brittleness is challenging in production processes like physical vapor deposition processes, especially in roll-to-roll production. In many cases, multiple geometric deformations take place and each step, like coating or cutting, influences the glass strength. By now, the relation between the strength of ultra-thin glass under quasi-static conditions and its strength under cyclic load has not been studied. Moreover, the effect of coatings has not been investigated. Both aspects are crucial to design reliable production processes. Therefore, the strength of ultra-thin glass under cyclic load was studied for uncoated and coated substrates. Two coating types were investigated: a single indium tin oxide film and a seven-layer antireflective layer stack. The coatings significantly influence the strength of the underlying glass in both test modes. The barrier properties, thin film stress, and the morphology/crystalline structure are identified as the major characteristics influencing the strength. [ABSTRACT FROM AUTHOR]

The recent advances in the area of electrophotocatalysis (EPC) show that it is a highly suitable technique to yield greener and more sustainable organic synthesis. The overall productivity of EPC however is constrained by a multitude of practical limitations, which impose difficulties in effectively harmonizing the photochemical and electrochemical steps, let alone in accelerating both steps simultaneously. In this contribution, we have tackled these limitations by developing a parallel plate flow cell that permits the execution of EPC in continuous flow. By using a transparent electrode, such as fluorine-doped tin oxide (FTO) or indium tin oxide (ITO) coated glass, the interelectrode distance could be reduced while improving photon absorption. By enhancing both the photochemical and electrochemical steps simultaneously, a notable increase in productivity and space–time-yield (a ten-fold and 300-fold improvement, respectively) of the N-arylation of different azoles was observed. In addition, this was achieved in a single-pass process under electrolyte-free conditions. Highlights: • We have created a flow cell that incorporates a transparent electrode, allowing simultaneous photochemical and electrochemical activation. • By using a parallel energy input, a productivity increase for the N-arylation of different azoles under electrolyte-free conditions was observed. • A single pass sufficed to reach high conversions, rendering this a true continuous flow process. [ABSTRACT FROM AUTHOR]

Ag nanowire electrodes are promising substitutes for traditional indium tin oxide (ITO) electrodes in optoelectronic applications owing to their impressive conductivity, flexibility, and transparency. This review provides an overview of recent trends in Ag nanowire electrode layer formation, including key developments, challenges, and future prospects. It addresses several challenges in integrating Ag nanowires into practical applications, such as scalability, cost-effectiveness, substrate compatibility, and environmental considerations. Additionally, drawing from current trends and emerging technologies, this review explores potential avenues for improving Ag nanowire layer-forming technologies, such as material advancements, manufacturing scalability, and adaptability to evolving electronic device architectures. This review serves as a resource for researchers, engineers, and stakeholders in nanotechnology and optoelectronics, and underscores the relationship between advancements in patterning and the application of Ag nanowire electrodes. Through an examination of key developments, challenges, and future prospects, this review contributes to the collective knowledge base and encourages continued innovation in the ever-evolving realm of Ag nanowire-based optoelectronics. [ABSTRACT FROM AUTHOR]

In the marine environment, the symbiotic relationship between Symbiodinium and corals plays a pivotal role in coral growth and development. Against the backdrop of widespread coral bleaching due to the global climate change, the facile and efficient separation and enrichment of different strains of Symbiodinium hold significant importance for studying coral bleaching. This paper aims to report a platform that integrates dielectrophoretic and inertial forces for the separation and enrichment of Symbiodinium, comprising two modular components: a separation module and an enrichment module. Within the separation module, distinct strains of Symbiodinium undergo preliminary stratification in a contraction–expansion microchannel under the influence of inertial forces. Dielectrophoretic forces generated by the indium tin oxide electrodes divert them toward different outlets, achieving separation. In the enrichment module, the Symbiodinium collected from outlets is rapidly focused through a contraction–expansion microchannel and high-purity samples are concentrated through a single outlet. Evaluating separation efficiency is based on the purity of collected Symbiodinium at the outlet under three different flow rates: 13, 16, and 19 μl/min, while the concentration of enriched Symbiodinium at 100, 200, 300, and 400 μl/min flow rates evaluates the effectiveness of the enrichment process. The experimental results demonstrate a separation purity of approximately 90% and an enrichment factor of around 5.5. The platform holds promise for further applications in the selection and targeted enrichment of high-quality coral symbiotic algae, providing essential research foundations for the conservation of coral ecosystems. [ABSTRACT FROM AUTHOR]

To establish the optimal processing parameters, it is imperative to gain an understanding of the interactions and ablation mechanisms between the picosecond pulsed laser and indium tin oxide (ITO) films. This research employed a picosecond pulsed laser for rear-side ablation of ITO films on polyethylene terephthalate (PET) substrates. A two-dimensional simulation temperature analysis of groove morphology was used to evaluate the elimination of ITO films through thermal evaporation. A methodical study was conducted on the effect of various laser processing parameters on the quality of the etched groove on the film's surface. The results highlighted the importance of combining laser power and scanning speed harmoniously to achieve superior groove performance. An increase in laser power coupled with a decrease in scanning speed resulted in a widening of laser grooves, increase in molten ridge heights, and a sharper line at the edge of grooves. At a scanning speed of 3000 mm/s and a power level of 1.10 W, optimal laser processing parameters were determined. This caused the groove's edges to display precision, the molten ridge height to be minimized, the groove width to measure 24.7 mm, and the groove termini to be completely separated. The characteristics of these discernible grooves coincide with the requirements for pragmatic groove applications. [ABSTRACT FROM AUTHOR]

Two new Schiff base compounds of N‐{2‐[(E)‐сyclohexyliminomethyl]phenyl}‐4‐methylbenzenesulfonamide, N‐{2‐[(E)‐(4‐сyclohexylphenyl)iminomethyl]phenyl}‐4‐methylbenzenesulfonamide and their Zn(II) complexes have been synthesized and characterized by elemental analysis, FT‐IR and UV–Vis spectra, and single crystal X‐ray determination. In both complexes, Zn2+ ions have a tetrahedral environment with two nitrogen atoms of the tosylamide groups and two nitrogen atoms of the imine fragment. Time‐dependent density functional theory calculations have been performed on two zinc(II) complexes in order to assign their experimental UV–visible absorption bands. Zinc(II) complexes showed thermal stability up to 335–340°C under a nitrogen atmosphere by thermogravimetric analysis (TGA). The photoluminescent spectra show that both Zn(II) complexes in the solid state at room temperature emit blue luminescence with high emission quantum yields of 20% and 29%. The doped devices with configurations of indium tin oxide (ITO)/poly(3,4‐ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS)/N,N′‐Di(1‐naphthyl)‐N,N′‐diphenyl‐(1,1′‐biphenyl)‐4,4′‐diamine (NPD)/4,4′‐N,N′ ‐dicarbazolebiphenyl (CBP):Zinc(II) complex (5%)/1,3,5‐tris(N‐phenylbenzimidazole‐2‐yl) benzene (TPBI)/LiF/Al have been fabricated and investigated. The doped device based on the complex with the сyclohexylphenyl substituent of the ligand showed the best electroluminescent characteristics with maximum brightness Lmax of 3415 cd/m2, maximum current efficiency of 2.8 cd/A, and power efficiency of 1.9 lm/W, while the doped device with emitter on the base of the complex with the сyclohexyl substituent showed slightly worse electroluminescence (EL) performance with Lmax of 2105 cd/m2, maximum current efficiency of 2.1 cd/A, and power efficiency of 1.6 lm/W. [ABSTRACT FROM AUTHOR]

Photoelectric catalysis is a green and efficient way to degrade pollutants, which has been paid more and more attention by researchers. Among them, Bi2WO3 has been proved to have excellent photocatalytic oxidation activity on its {001} facets. In this study, {001}-oriented facets with high exposure were successfully integrated into Bi2WO6 nanoplate arrays (Bi2WO6 NAs) to create a photoelectrode. This structure was grown in situ on an indium tin oxide (ITO) substrate. To promote photogenerated carrier separation efficiency and reduce agglomeration of Bi2WO6 photocatalysts, the electrochemical deposition of NiFe–layered double hydroxide (NiFe-LDH) and Ti3C2 (MXene) were introduced in this research to synergistically catalyze pollutant degradation. Morphology, spectral characterization, and electrochemical analysis jointly confirmed that the outstanding performance of hole capture behavior with LDH and electron conduction properties with MXene were the main reasons for the improvement in catalytic activity of the photoelectrode. Taking bisphenol A (BPA) as the model pollutant, the rate constant k of the NiFe-LDH/Ti3C2/Bi2WO6 NAs photoelectrode reaches 0.00196 min−1 under photoelectrocatalytic (PEC) conditions, which is 4.5 times that of the pure Bi2WO6 NAs photoelectrode. This work provides a new way to improve the reaction kinetics of the PEC degradation of pollutants. [ABSTRACT FROM AUTHOR]

This paper proposed a single-layer checkerboard metasurface with simultaneous wideband radar cross-section (RCS) reduction characteristics and low infrared (IR) emissivity. The metasurface consists of an indium tin oxide (ITO)-patterned film, a polyethylene terephthalate (PET) substrate and an ITO backplane from the top downwards, with a total ultra-thin thickness of 1.6 mm. This design also allows the metasurface to have good optical transparency and flexibility. Based on phase cancellation and absorption, the metasurface can achieve a wideband RCS reduction of 10 dB from 10.6 to 19.4 GHz under normal incidence. When the metasurface is slightly cylindrically curved, an RCS reduction of approximately 10 dB can still be achieved from 11 to 19 GHz. The polarization and angular stability of the metasurface have also been verified. The filling rate of the top ITO-patterned film is 0.81, which makes the metasurface have a low theoretical IR emissivity of 0.24. Both simulation and experimental results have verified the excellent characteristics of the proposed checkerboard metasurface, demonstrating its great potential application in radar–IR bi-stealth. [ABSTRACT FROM AUTHOR]

A passive wireless high-temperature sensor for far-field applications was developed for stable temperature sensing up to 1000 °C. The goal is to leverage the properties of electroceramic materials, including adequate electrical conductivity, high-temperature resilience, and chemical stability in harsh environments. Initial sensors were fabricated using Ag for operation to 600 °C to achieve a baseline understanding of temperature sensing principles using patch antenna designs. Fabrication then followed with higher temperature sensors made from (In, Sn) O2 (ITO) for evaluation up to 1000 °C. A patch antenna was modeled in ANSYS HFSS to operate in a high-frequency region (2.5–3.5 GHz) within a 50 × 50 mm2 confined geometric area using characteristic material properties. The sensor was fabricated on Al2O3 using screen printing methods and then sintered at 700 °C for Ag and 1200 °C for ITO in an ambient atmosphere. Sensors were evaluated at 600 °C for Ag and 1000 °C for ITO and analyzed at set interrogating distances up to 0.75 m using ultra-wideband slot antennas to collect scattering parameters. The sensitivity (average change in resonant frequency with respect to temperature) from 50 to 1000 °C was between 22 and 62 kHz/°C which decreased as interrogating distances reached 0.75 m. [ABSTRACT FROM AUTHOR]

Metallosupramolecular polymers (MSPs) have reversible electrochromic (EC) characteristics. Transition metal ions and ditopic organic ligands are complexed 1:1 to form MSPs, but the complexation conditions depend on the metal species ions. Herein, a microwave‐assisted (MWA) quick synthesis of a Ru(II)‐based MSP (polyRu–MWA) as a novel preparation method for MSPs is reported. PolyRu–MWA is synthesized under microwave irritation for 60 min using 770 W and 2.45 GHz frequency, whereas a conventionally synthesized Ru(II)‐based MSP (polyRu–CS) is obtained using oil‐bath at 160 °C for 24 h. PolyRu–MWA is found to show much better EC properties than polyRu–CS. A film of polyRu–MWA prepared on an indium tin oxide glass exhibits higher optical contrast (transmittance change, ΔT: 81.39%) than polyRu–CS (67.73%). Coloration efficiency(CE, η) of polyRu–MWA (425.7 cm2 C−1) is also higher than that of polyRu–CS (318.3 cm2 C−1). Interestingly, the charge and discharge current ratio for bleaching and coloring in polyRu–MWA is ≈1.7 times higher than that for polyRu–CS, probably because of the high molecular weight polymer formation in polyRu–MWA. A polyRu–MWA film also displays a longer EC optical memory than polyRu–CS. [ABSTRACT FROM AUTHOR]

This paper designs and validates a composite functional metasurface that combines microwave absorption and vibrational energy harvesting. The metasurface is composed of an indium tin oxide (ITO) electrically conductive glass pattern layer, arrays of 1‐ethyl‐3‐methylimidazolium dicyanamide [EMIM][N(CN)2] droplets, and an underlying indium tin oxide (ITO) electrically conductive glass layer. The composite functional metasurface possesses broadband absorption performance when the microwave frequency bands are between 7.34 and 22.63 GHz, which can transform vibration energy into electrical energy simultaneously. The relationship between output power, the number of droplets, internal resistance, and the matching load of the composite functional metasurface is deeply studied. It is found that the internal resistance decreases with the increase in the number of droplet arrays. The effective output power reaches up to 125nW when there are 48 droplet arrays. This technology has promising applications in the field of intelligent and portable electromagnetic devices. [ABSTRACT FROM AUTHOR]

A flexible, transparent and polarization-insensitive metasurface absorber (MA) with dual-broadband feature is proposed. The MA consists of absorption layer, transparent flexible polyvinyl chloride (PVC) dielectric layer, and indium tin oxide (ITO)/polyethylene terephthalate (PET) bottom plate. The dual-broadband characteristics are studied by transmission-line theory, numerical simulation and experiment. The experimental results indicate that over 90% absorptivity under the planar case is achieved in 10.85–26.01 GHz and 44.86–56.67 GHz, corresponding relative bandwidth are 82.23% and 23.26%, respectively. The light transmittance is 63.3%. Both theoretical analysis and simulated results are good accordance with the experiment. The influence of structural parameters on the dual-broadband absorption performance is studied. Moreover, the analysis of the impedance matching theory, surface current, magnetic field and electric field distributions and power loss density are given to explain the dual-band absorption mechanism. The proposed dual-broadband MA maintains good angular stability whether in planar (30°) or conformal (20°) cases. The MA has simple structure, high optical transparency and flexibility, it promises to be a good candidate for electromagnetic (EM) shielding room observation windows, touch panel controls, radio-frequency identification systems and transparent radio-frequency devices. [ABSTRACT FROM AUTHOR]

We report the fabrication and characterization of a plasmonic metasurface comprising electrically-contacted sub-wavelength gold dipole nanoantennas, conformally coated by a thin hafnia film, an indium tin oxide layer and a backside mirror, forming metal–oxide–semiconductor (MOS) capacitors, for use as an electrically-tunable reflectarray or metasurface. By voltage biasing the nanoantennas through metallic connectors and leveraging the carrier refraction effect in the MOS capacitors, our measurements demonstrate phase control in reflection over a range of about 30°, with a constant magnitude of reflection coefficient of 0.5, and the absence of secondary lobes. Comprehensive electromagnetic and quantum carrier models of the structure are developed and are in excellent agreement with the measurements. The metasurface holds promise for use as an optical phased array.

This article presents the optical analysis on how the light coupling performance between optical channel waveguides and gold periodic nanoarrays in the visible spectrum can be improved using an indium tin oxide (ITO) thin film as buffer layer. Coupling efficiency, out-of-plane scattering and far-field projected beam focus and diffraction angle are evaluated using Finite-Difference Time-Domain (FDTD) method and scattering theory for different nanogratings and nanocylinders array patterns. The implementation of ITO enables up to a 12 fold increase in coupling efficiency, a 6.4 fold enhancement of light scattered out of the array plane and consequent improvements in the diffracted beam radiation intensity peaks, without compromising the beam's focus or altering its deflection angle. This configuration provides a cheap and simple solution to increase the device performance without changing the array features, for integrated biosensing and scattering-related applications.

Lossy mode resonance (LMR) has garnered significant attention in sensor applications. LMR was primarily explored in fiber-based systems, however, there has been a recent upsurge in its application within planar waveguides. This article compares the LMR phenomenon in planar waveguides with the most employed coatings in the field, specifically SnO2, TiO2, and ITO. Additionally, the experimental findings are compared with simulations conducted using the finite element method (FEM) within the COMSOL Multiphysics environment. The novelty of this research lies in the integration of both experimental results and theoretical calculations, utilizing strong FEM simulation tools, in a single study.

In this article, we present the structural investigation by Raman spectroscopy of GeSbSeN ovonic threshold switching (OTS) material once integrated in selector devices featuring a top electrode based on a transparent and conductive indium tin oxide layer. The devices are characterized by standard electrical protocols, and the structural evolution of the material is investigated after several switching operations. The results are correlated with the spectra obtained from blanket samples annealed at increasing temperature and are supported by XRD and TEM analyses. We establish a link between the evolution of the material structure with the annealing process and the device behavior along cycling, bringing important advancement in the understanding of the switching mechanism and of the origin of the failure in OTS devices. [ABSTRACT FROM AUTHOR]

We report on metalorganic vapor phase epitaxy of highly conductive germanium-doped GaN layers and their application for blue tunnel-junction light emitting diodes (TJ-LEDs). Using Ge as donor, carrier densities of up to 2 × 1020 cm−3 and low bulk resistivities down to 3 × 10−4 Ωcm are achieved. Under optimum growth conditions, no degradation of the crystalline quality is observed and layers exhibit high transparency making GaN:Ge very attractive as current spreading layer in light emitting devices. We have realized GaN-based TJ-LEDs by capping conventional InGaN LED structures with highly doped GaN:Ge. Such TJ-LEDs withstand operation currents up to 20 kA/cm2 in continuous and up to 60 kA/cm2 in pulsed operation conditions. Moreover, TJ-LEDs exhibit homogeneous electroluminescence and light output through the top surface that is increased by more than 60% as compared to conventional LEDs with transparent indium tin oxide contacts. The impact of the doping profile, carrier gas conditions, and acceptor activation by annealing for low-resistive TJ characteristics is discussed. Light output and current voltage characteristics of blue-light emitting devices with GaN-TJ are presented at low and high-current densities. [ABSTRACT FROM AUTHOR]

The internal electron transport capacity of the semiconductor directly affects whether there is a sufficient number of photogenerated electrons involved in the catalytic reaction process, thus determining the photocatalytic efficiency. Indium tin oxide (ITO), as an excellent conductive material, has convenient internal electron transport and can be used as a good photocatalyst directly. In this paper, ITO films on three different conductive substrates were prepared by DC sputtering method, and the crystallization and appearance of each sample were compared. Different substrates affect the energy band position of catalyst. The performance of photocatalytic CO 2 reduction was tested. We found that ITO films grown on carbon cloth (CC) substrate have good photocatalytic properties. The atmosphere ratio in the preparation process also has a certain influence on the performance of the sample. Compared with ITO conductive glass widely used in the market, our improved ITO film has better photocatalytic properties and practicability. This work provides a certain reference for the application of ITO in the field of photocatalysis. [ABSTRACT FROM AUTHOR]

Heavy metal ion pollution and pharmaceutical contamination pose severe threats to public health and the environment, necessitating the development of a highly efficient dual-functional electrochemical sensing material capable of detecting both heavy metal ions and pharmaceutical pollutants. In this investigation, we employed a simple hydrothermal method to grow a Ni 5 P 4 /Ni 2 P/C network-like nanosheet arrays on indium tin oxide (ITO) glass, successfully fabricating a dual-functional non-enzyme electrochemical sensor capable of detecting Cu2+ and Paracetamol (PA). The interconnected and uniform network structure of Ni 5 P 4 /Ni 2 P/C nanosheets vertically grows on the ITO substrate, forming a well-ordered nanosheet arrays. In a 0.1 M HAC-KAC (pH = 5.6) buffer solution, Ni 5 P 4 /Ni 2 P/C/ITO exhibits an ultra-wide linear range (31.25 pM–218.75 μM) and an ultra-low detection limit (10 pM) for Cu2+, along with excellent anti-interference ability, repeatability, and stability. In a buffer solution of 0.1 M PBS (pH = 7.4), Ni 5 P 4 /Ni 2 P/C/ITO displays a broad linear range (0.1–220 μM) and a low detection limit (30 nM) for PA, as well as good anti-interference ability, reproducibility, and stability. These remarkable sensing capabilities are primarily attributed to the small charge transfer resistance, large electrochemical active area, and abundant active sites of the electrode material. [ABSTRACT FROM AUTHOR]

Epsilon-near-zero (ENZ) materials have gained recent interest due to their exotic optical properties, but their potential is limited by intrinsic material losses. Enhanced epsilon-near-zero (eENZ) materials are periodically stratified media consisting of alternating ENZ and dielectric layers. In this study, we demonstrate the fabrication and optical characterization of 15-layer ENZ-dielectric thin film stack, wherein indium tin oxide functions as the ENZ material and titanium dioxide as the dielectric. We experimentally show the enhanced optical transmission of the structure over a bare ENZ film with similar thickness. Further, we display the giant polarization dependent optical response of the material, which is characterized by the narrowing from 56° to 14° in half-width at half-maximum of the transmission cone. These properties are physically attributed to guided-waves, Fabry–Pérot resonances, and Ferrell–Berreman plasmons within the film stack. The experimental realization of our material paves the way for devices utilizing eENZ-materials, such as coherence switchable lasers and light sources with directional emission. [ABSTRACT FROM AUTHOR]

The title compound, unimer U (tpy stands for 2,2′:6′,2″-terpyridin-4′-yl end-group), by itself shows the memristor effect with a retention time of 18 h and persistence of 11 h. Its coordination copolymer with Co(II) ions, [CoU]n, exhibits multimodal resistance changes similar to the synaptic responses observed in biological systems. More than 320 cycles of potentiation and depression measured in continuous sequence occurred without observing a significant current change, confirming the operational stability and reproducibility of the device based on the [CoU]n polymer. The synaptic effect of a device with an indium tin oxide (ITO)/[CoU]n/top-electrode (TE) configuration is more pronounced for the device with TE = Au compared to devices with TE = Al or Ga. However, the latter TEs provide a cost-effective approach without any significant compromise in device plasticity. The detected changes in the synaptic weight, about 12% for pair-pulse facilitation and 80% for its depression, together with a millisecond trigger and reading pulses that decay exponentially on the time scale typical of neurosynapses, justify the device's ability to learn and memorize. These properties offer potential applications in neuromorphic computation and brain-inspired synaptic devices. [ABSTRACT FROM AUTHOR]

This work has presented gas sensors based on indium tin oxide (ITO) for the detection of SO2 and NO2. The ITO gas-sensing material was deposited by radio frequency (RF) magnetron sputtering. The properties of gas sensing could be improved by increasing the ratio of SnO2. The response characteristics of the gas sensor for detecting different concentrations of NO2 and SO2 were investigated. In the detection of NO2, the sensitivity was significantly improved by increasing the SnO2 ratio in ITO by 5%, and the response and recovery time were reduced significantly. However, the sensitivity of the sensor decreased with increasing SO2 concentration. From X-ray photoelectron spectroscopy (XPS) analysis, the gas-sensitive response mechanisms were different in the atmosphere of NO2 and SO2. The NO2 was adsorbed by ITO via physisorption but the SO2 had a chemical reaction with the ITO surface. The gas selectivity, temperature dependence, and environmental humidity of ITO-based gas sensors were systematically analyzed. The high detection sensitivity for acidic gas of the prepared sensor presented great potential for acid rain monitoring. [ABSTRACT FROM AUTHOR]

By combining the switching ability of redox molecules with the unique fluorescence properties of quantum dots (QDs), a robust electrochemical fluorescence switch is developed here. This is realized by grafting CdSe/ZnS QDs on transparent indium tin oxide (ITO) substrates and, subsequently, modifying them with a Ferrocene (Fc) molecular monolayer. The application of oxidation/reduction voltage pulses to tune the Fc redox state leads to the tuning of the surface fluorescence output. Interestingly, the ON/OF ratio can be enhanced by reducing the distance between the redox active unit and the QD due to a more efficient electronic coupling. Remarkably, by defining a mixed‐valence state, a ternary switch has also been achieved. It is highlighted that the QD surface immobilization is key to realize this switch to avoid aggregation and fluorescence quenching in suspension. Hence, an efficient and versatile novel route to fabricate robust fluorescent redox switches is demonstrated, opening a wide avenue of possibilities to be explored in the field of sensing and information storage. [ABSTRACT FROM AUTHOR]

The realization of a controllable transparent conducting system with selective light transparency is crucial for exploring many of the most intriguing effects in top‐illuminated optoelectronic devices. However, the performance is limited by insufficient electrical conductivity, low work function, and vulnerable interface of traditional transparent conducting materials, such as tin‐doped indium oxide. Here, it is reported that two‐dimensional (2D) titanium carbide (Ti3C2Tx) MXene film acts as an efficient transparent conducting electrode for the lead sulfide (PbS) colloidal quantum dots (CQDs) photodiode with controllable near infrared transmittance. The solution‐processed interface engineering of MXene and PbS layers remarkably reduces the interface defects of MXene/PbS CQDs and the carrier concentration in the PbS layer. The stable Ti3C2Tx/PbS CQDs photodiodes give rise to a high specific detectivity of 5.51 × 1012 cm W−1 Hz1/2, a large dynamic response range of 140 dB, and a large bandwidth of 0.76 MHz at 940 nm in the self‐powered state, ranking among the most exceptional in terms of comprehensive performance among reported PbS CQDs photodiodes. In contrast with the traditional photodiode technologies, this efficient and stable approach opens a new horizon to construct widely used infrared photodiodes with CQDs and MXenes. [ABSTRACT FROM AUTHOR]

To overcome the Shockley–Queisser limit, studies have focused on improving the efficiency of perovskite solar cells (PSCs) through several optimization and tandem‐structure design strategies. Furthermore, the significance of emerging transparent front electrodes (TFEs), which exert a direct and substantial influence on the performance of PSCs, is on the rise. Therefore, further research must be conducted to validate these effects in improving the existing performance of PSCs. Thus, this study developed a composition‐engineered indium tin oxide (CE‐ITO) TFE that outperforms commercial ITO (C‐ITO; 10 at.% Sn doped ITO) for efficient and stable PSCs. The CE‐ITO electrode (7.50 at.% Sn doped ITO) has a large columnar structure and good thermal stability, which are ideal for high‐performance PSCs. Compared to C‐ITO, CE‐ITO has a smoother surface, higher conductivity, lower resistivity, and improved optical transmittance in the active layer. These contribute to the larger perovskite active‐ and electron‐transport layers, less active‐layer degradation, and lower shunt resistance. The various merits of CE‐ITO enable high‐performance PSCs with a maximum power conversion efficiency of 23.35% and long‐term stability by simply substituting C‐ITO with optimal CE‐ITO. [ABSTRACT FROM AUTHOR]

Near-field radiative heat transfer (NFRHT) can overcome the blackbody radiation limit and holds great promise in radiative energy conversion devices such as near-field thermophotovoltaics (NF-TPV). However, NF-TPV is not yet ready for practical applications at larger scales due to the challenges of maintaining the nanoscale gap and the lack of optimized NFRHT with nanostructure emitters. Here, we measure the enhanced near-field radiative heat flux between GaSb absorbers and nanostructure emitters that can be applied in NF-TPV systems, with a cm2-scale plate–plate structure and a temperature difference of 100 K at a gap down to 200 nm. It is demonstrated that the radiative heat flux between the bulk W emitter and the absorber at a 400 nm gap is about an order of magnitude larger than that in the far field, and the heat flux can be further enhanced by 1.6 times at a 200 nm gap. Moreover, the enhanced NFRHT from the surface plasmon polaritons supported by a indium tin oxide film and the hyperbolic modes supported by a W/SiO2 multilayer is also experimentally verified and theoretically analyzed. [ABSTRACT FROM AUTHOR]

Recently, materials with vanishingly small permittivity, known as epsilon‐near‐zero (ENZ) media, emerged as promising candidates to achieve nonlinear optical effects of unprecedented magnitude on a solid‐state platform. In particular, the ENZ behavior of indium tin oxide (ITO) thin films resulted in Kerr‐type nonlinearity with non‐perturbative refractive index variations that are key to developing more efficient Si‐compatible devices with sub‐wavelength dimensions. In this contribution, exceptional enhancement of the nonlinear index variation of 30 nm‐thick ITO nanolayers by silicon dioxide/silicon nitride (SiO2/SiN) Tamm plasmon‐polariton structures fabricated by radio‐frequency magnetron sputtering on transparent substrates under different annealing conditions is proposed and demonstrated. In particular, the linear and nonlinear optical properties of ITO thin films and resonant photonic structures are investigated using broadband spectroscopic ellipsometry and intensity‐dependent Z‐scan nonlinear characterization, demonstrating enhancement of optical nonlinearity with refractive index variations as large as Δn ≈ 2 in the non‐perturbative regime. This study reveals that the efficient excitation of strongly confined plasmon‐polariton Tamm states substantially boosts the nonlinear optical response of ITO nanolayers, providing a stepping stone for the engineering of more efficient infrared devices and nanostructures for a broad range of applications, including all‐optical data processing, nonlinear spectroscopy, sensing, and novel quantum detection modalities. [ABSTRACT FROM AUTHOR]

Thin film samples like transparent conducting oxides (TCO) are typically investigated using measurements like Hall Effect and 4-point probe measurements. We use a sensitive AC Faraday rotation (FR) setup to study thin film samples for which a magneto-optic response is challenging to characterize. The experimental setup employs a stabilized He-Ne laser (633 nm) along with an AC magnetic field that enables lock-in detection. We investigate a series of TCO samples that are deposited on a glass substrate. The TCO samples include the more widely used Indium Tin Oxide (ITO) and the relatively newer Fluorine doped Tin Oxide films, usually referred to as FTO. These films have a magneto-optic response due to the presence of free carrier concentration and therefore measurement of this response (Verdet constant) could allow one to determine the carrier concentration of these films. Given that magneto optic responses like FR depend on the length of the sample length traveled by light, these sub-micron films pose considerable challenges in trying to extract the FR response of the film from that of the much thicker glass substrate. Furthermore, we present details of the design and FR characterization of samples using a Michelson interferometer-based measurement setup which enhances the Faraday rotation and affords a new means of studying harmonic peaks of the recorded optical signal in response to a sinusoidally-varying applied magnetic field. We compare some early results from this setup to the typical "single-pass" setup to highlight the difference in the recorded signals from the two setups. To showcase the advantages of the proposed measurements, we also include some early results from a very different type of sample, namely superparamagnetic nanoparticles (SNPs). [ABSTRACT FROM AUTHOR]