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Abstract Antiferroelectric thin films hold significant potential for bringing novel physics phenomena and fascinating properties. Their applications are often intertwined with the antiferroelectric‐ferroelectric phase transition, which is contingent on the chemical compositions of the constituent material. Nevertheless, the prevailing trial‐and‐error‐based research methodology is ill‐suited for the exploration of the relationship between chemical compositions and the antiferroelectric‐ferroelectric phase transition. To address this challenge, a high‐throughput synthesis strategy for antiferroelectric thin films is presented, which is enabled by an advanced high‐throughput pulsed laser deposition technology. The effectiveness of this synthesis strategy using (Pb1−XBaX)ZrO3 and achieving precise control over the parameter X is showcased. This approach allows for the deposition of (Pb1−XBaX)ZrO3 thin films encompassing nine chemical compositions ranging from X = 0 to X = 0.08. Based on this high‐throughput method, the composition that corresponds to the phase transition of (Pb1−XBaX)ZrO3, falling within the range of X = 0.04 to X = 0.06 is pinpointed. Furthermore, a temperature‐dependent correlation between the phase transition and chemical composition is established. This work not only presents a practical routine for establishing a comprehensive map of material chemical composition in relation to the properties of antiferroelectric thin films but also offers a method for the high‐throughput exploration of complex oxide thin films.

Iron ion is the common transition metal ion in atmospheric aerosol, which can affect the components and optics of secondary organic aerosol (SOA). In the current study, the atmospheric photooxidation of toluene to produce SOA in the presence of ferric chloride fine particles is simulated in a smog chamber; on-line and off-line mass spectrometry and spectroscopic instruments are used to characterize constituents and optics of SOA. Compare with SOA formed in the absence of fine particles, the laser desorption/ionization mass spectra of toluene SOA generated in the presence of ferric chloride fine particles show ion peaks of m/z = 163 and 178, the UV-Vis spectra of the extracting solution for toluene SOA have peaks near 400 and 700 nm, and the electrospray ionization mass spectra contain peaks at m/z = 248 and 300. Based on this spectral information, it is shown that gaseous methylcatechol formed from photooxidation of toluene may react with iron ion on the surface of fine particles by complexing and oxidation–reduction, resulting in methylbenzoquinone products and metallo-organic complex ions such as [Fe(III)(CH3C6H3OO)]+, [Fe(III)(CH3C6H3 OO)2]− and [Fe(III)(CH3C6H3OO)Cl2]−. These products have strong light absorption ability, resulting in an increase in the averaged mass absorption coefficient () in the 200~1000 nm range and the MAC at 365 nm (MAC365) for toluene SOA, while and MAC365 progressively increase with an increasing concentration of ferric chloride fine particles. These results serve as experimental references for the study of the formation mechanism and optical properties of metallo-organic complexes in atmospheric aerosol particles in regions experiencing high levels of fine particles of metal and automobile exhaust pollution.

Ternary logic has been proven to carry an information ratio 1.58 times that of binary logic and is capable to reduce circuit interconnections and complexity of operations. However, the excessive transistor count of ternary logic gates has impeded their industry applications for decades. With the modulation of the ferroelectric negative capacitance (NC) properties on the channel potential, MOSFETs show many novel features including steep subthreshold swing and non-saturation output characteristics, based on which an ultra-compact ternary inverter can be achieved. Compared with traditional bulk materials, layered 2D materials and 2D ferroelectrics provide a clean interface and better electrostatic control and reliability. Even though ultra-low SS (∼10 mV/dec) has been experimentally demonstrated in ferroelectric-negative capacitance-incorporated 2D semiconductor (NC2D) FETs, the available models are still rare for large-scale circuit simulations. In this study, the superb electrical properties of pure 2D material stack-based NC2D FETs (layered CuInP2S6 adopted as the 2D ferroelectric layer) are investigated through device modeling based on the Landau–Khalatnikov (LK) equations in HSPICE. We managed to realize an ultra-compact ternary inverter with one NC2D-PMOS (WSe2) and one NC2D-NMOS (MoS2) in HSPICE simulations, whose transistor count is significantly reduced compared with other counterparts. We also proposed a novel input waveform scheme to solve the hysteresis problem caused by ferroelectric modulation to avoid logic confusion. Additionally, the power consumption and propagation delay of the NC2D-based ternary inverter are also investigated. This work may provide some insights into the design and applications of ferroelectric-incorporated 2D semiconductor devices.

Memristors offer great advantages as a new hardware solution for neuromorphic computing due to their fast and energy‐efficient matrix vector multiplication. However, the nonlinear weight updating property of memristors makes it difficult to be trained in a neural network learning process. Several compensation schemes have been proposed to mitigate the updating error caused by nonlinearity; nevertheless, they usually involve complex peripheral circuits design. Herein, stochastic and adaptive learning methods for weight updating are developed, in which the inaccuracy caused by the memristor nonlinearity can be effectively suppressed. In addition, compared with the traditional nonlinear stochastic gradient descent (SGD) updating algorithm or the piecewise linear (PL) method, which are most often used in memristor neural network, the design is more hardware friendly and energy efficient without the consideration of pulse numbers, duration, and directions. Effectiveness of the proposed method is investigated on the training of LeNet‐5 convolutional neural network. High accuracy, about 93.88%, on the Modified National Institute of Standards and Technology handwriting digits datasets is achieved (with typical memristor nonlinearity as ±1), which is close to the network with complex PL method (94.7%) and is higher than the original nonlinear SGD method (90.14%).

Imidazole compounds are important constituents of atmospheric brown carbon. The imidazole components of aqueous secondary organic aerosol (aqSOA) that are generated from the evaporation of droplets containing pyruvaldehyde and inorganic ammonium are on-line characterized by an aerosol laser time-of-flight mass spectrometer (ALTOFMS) and off-line detected by optical spectrometry in this study. The results demonstrated that the laser desorption/ionization mass spectra of aqSOA particles that were detected by ALTOFMS contained the characteristic mass peaks of imidazoles at m/z = 28 (CH2N+), m/z = 41 (C2H3N+) and m/z = 67 (C3H4N2+). Meanwhile, the extraction solution of the aqSOA particles that were measured by off-line techniques showed that the characteristic absorption peaks at 217 nm and 282 nm appeared in the UV-Vis spectrum, and the stretching vibration peaks of C-N bond and C=N bond emerged in the infrared spectrum. Based on these spectral information, 4-methyl-imidazole and 4-methyl-imidazole-2-carboxaldehyde are identified as the main products of the reaction between pyruvaldehyde and ammonium ions. The water evaporation accelerates the formation of imidazoles inside the droplets, possibly owing to the highly concentrated environment. Anions, such as F−, CO32−, NO3−, SO42− and Cl− in the aqueous phase promote the reaction of pyruvaldehyde and ammonium ions to produce imidazole products, resulting in the averaged mass absorption coefficient () in the range of 200–600 nm of aqSOA increases, and the order of promotion is: F− > CO32− > SO42− ≈ NO3− ≈ Cl−. These results will help to analyze the constituents and optics of imidazoles and provide a useful basis for evaluating the formation process and radiative forcing of aqSOA particles.

The OH-initiated reaction of ethylbenzene results in major OH addition, and the formed ethylbenzene-OH adducts subsequently react with O2 and NO2, which determine the components of the oxidation products. In this study, nine possible reaction paths of the most stable ethylbenzene-OH adduct, EB-Ortho (2-ethyl-hydroxycyclohexadienyl radical intermediate), with O2 and NO2 were studied using density functional theory and conventional transition state theory. The calculated results showed that ethyl-phenol formed via hydrogen abstraction was the major product of the EB-Ortho reaction with O2 under atmospheric conditions. Peroxy radicals generated from O2 added to EB-Ortho could subsequently react with NO and O2 to produce 5-ethyl-6-oxo-2,4-hexadienal, furan, and ethyl-glyoxal, respectively. However, nitro-ethylbenzene formed from NO2 addition to EB-Ortho was the predominant product of the EB-Ortho reaction with NO2 at room temperature. The total calculated rate constant of the EB-Ortho reaction with O2 and NO2 was 9.57 × 10−16 and 1.78 × 10−11 cm3 molecule−1 s−1, respectively, approximately equivalent to the experimental rate constants of toluene-OH adduct reactions with O2 and NO2. This study might provide a useful theoretical basis for interpreting the oxygen-containing and nitrogen-containing organics in anthropogenic secondary organic aerosol particles.

Aromatic secondary organic aerosol (SOA) particles are known to contribute to radiative forcing and light absorption of atmosphere. However, the complex refractive index (CRI), single-scattering albedo (SSA) and other optical parameters of aromatic SOA are not well understood. SOA generated from photooxidation of toluene with a variety concentration of ammonium sulfate ((NH4)2SO4) seed particles in a smog chamber were investigated in the current study. The real part CRI of toluene SOA without seeds derived and based on aerosol albedometer measurements is 1.486 ± 0.002 at λ = 470 nm, showing a good agreement with available experimental data, and its SSA was measured to be 0.92 ± 0.02 at λ = 470 nm, indicating that the SOA particles without seeds have strong scattering ability. The SSA of SOA formed in the presence of 300 μg/m3 (NH4)2SO4 seed was 0.81 ± 0.02 at λ = 470 nm, less than the SSA of SOA without seed. SSA of SOA decreased, while the imaginary part of CRI (k) of SOA increased with increasing concentration of (NH4)2SO4 seed, demonstrating that the adsorption capacity of SOA formed in the presence of (NH4)2SO4 seed is enhanced. Different from the carboxyl compounds measured in the SOA without seed, imidazoles with strong chromophores of C=N that are responsible for the light absorption were detected as the principal constituents of SOA formed in the presence of (NH4)2SO4 seed. These would provide valuable information for discussing the optics and components of aromatic SOA in the urban atmosphere containing a high concentration of (NH4)2SO4 fine particles.

We investigate the topological bound modes of surface plasmon polaritons (SPPs) in a graphene pair waveguide array. The arrays are with uniform inter-layer and intra-layer spacings but the chemical potential of two graphene in each pair are different. The topological bound modes emerge when two arrays with opposite sequences of chemical potential are interfaced, which are analogous to Jackiw-Rebbi modes with opposite mass. We show the topological bound modes can be dynamically controlled by tuning the chemical potential, and the propagation loss of topological bound modes can be remarkably reduced by decreasing the chemical potential. Thanks to the strong confinement of graphene SPPs, the modal wavelength of topological bound modes can be squeezed as small as 1/70 of incident wavelength. The study provides a promising approach to realizing robust light transport beyond diffraction limit.

With the approaching end of Moore’s Law (that the number of transistors in a dense integrated circuit doubles every two years), the logic data density in modern binary digital integrated circuits can hardly be further improved due to the physical limitation. In this aspect, ternary logic (0, 1, 2) is a promising substitute to binary (0, 1) because of its higher number of logic states. In this work, we carry out a systematical study on the emerging two-dimensional (2D) materials (MoS2 and Black Phosphorus)-based ternary logic from individual ternary logic devices to large scale ternary integrated circuits. Various ternary logic devices, including the standard ternary inverter (STI), negative ternary inverter (NTI), positive ternary inverter (PTI) and especially the ternary decrement cycling inverter (DCI), have been successfully implemented using the 2D materials. Then, by taking advantage of the optimized ternary adder algorithm and the novel ternary cycling inverter, we design a novel ternary ripple-carry adder with great circuitry simplicity. Our design shows about a 50% reduction in the required number of transistors compared to the existing ternary technology. This work paves a new way for the ternary integrated circuits design, and shows potential to fulfill higher logic data density and a smaller chip area in the future.

Toluene and other aromatics can dissolve in atmospheric aqueous phases and undergo photooxidation reactions, forming secondary organic aerosol (SOA) after water evaporation. Copper ion is a typical heavy metal ion and is able to change the composition and optics of SOA. The reaction solution for OH-initiated photooxidation of toluene in presence of copper ions is atomized by TSI 9302, and the water is absorbed by silica gel to simulate the formation of aqueous SOA particles in this study. The composition and optics of the formed aqueous SOA are on-line and off-line, characterized by mass spectrometry and spectroscopy. Experimental results demonstrate that laser desorption/ionization mass spectra for aqueous SOA contain molecular ion peaks at m/z = 108, 124, and 140 for cresol, mehtyl dihydroxybenzene, and methyl trihydroxybenzene. The absorption peak intensity of phenolic compounds at 277 nm in the UV-Vis spectra of the collection solution for aqueous SOA increases, and electrospray ionization negative ion mass spectra show the polymer ion peak as high as m/z = 641. These indicate that copper ions catalyze the production of more phenolic compounds and hydroxyphenyl ether polymers formed by the polymerization of cresol. These products have the capacity for strong light absorption, leading to a significant increase in the averaged mass absorption coefficient () in 200-600 nm for aqueous SOA, which gently rises with an increment of copper ions. These provide the basis for studying the components and optics of aqueous SOA in presence of heavy metal ions. [ABSTRACT FROM AUTHOR]