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Negative charge card refrigeration, as a new solid-state refrigeration technology, has garnered much interest with its broad application potential in the area of temperature control for sensors and electronic devices. In this study, antiferroelectric thin films of Pb1−xMnxZrO3 (x = 0.0%, 0.5%, 1.0%, 2.0%, abbreviated as PMZ-100x) were prepared on tin oxide doped with fluorine/glass substrates by the sol-gel method. When the variable temperature P–E loops under various applied electric fields are compared, the P–E loops gradually change from linear to typical double P–E loops. This result implies that temperature and electric field work together to induce the phase change. The negative electrocaloric effect of the PMZ-0.5 film is greatly enhanced at 50 °C, 444 kV/cm, ΔS = 16.75 J·K−1·kg−1, ΔT = −16.39 K, in comparison to the PbZrO3 film (ΔS = 11.84 J·K−1·kg−1, ΔT = −12.48 K at 75 °C, 421 kV/cm). The great cooling performance indicates that PMZ-100x films have excellent potential for use in integrated circuit solid-state cooling. [ABSTRACT FROM AUTHOR]

Lutetium oxide (Lu2O3) has an ultra-wide bandgap of 5.5–6.2 eV and great potential for application in high-performance deep ultraviolet photodetectors (PDs). In this work, a strategy to improve the performance of Lu2O3-based DUV PDs is proposed, which makes use of the photo-induced pyro-phototropic effect and the photovoltaic effect (that is, the dual-field coupling effect) of the heterojunction. By constructing a Ti3C2Tx/Lu2O3 Schottky heterojunction and utilizing the photo-dual-field coupling effect induced at the heterojunction interface, an endogenous synergistic enhancement is realized in the efficiency of DUV optical absorption and photogenerated carrier separation. The Ti3C2Tx/Lu2O3/GaN DUV photodetector fabricated in this study exhibits excellent performance at 0 V bias, such as a high photoresponsivity (R ≈ 23.8 mA W−1) and a high response speed (decay time ∼40.3 ms). Under the same illumination conditions, the photoresponsivity of this device based on the dual-field coupling effect is higher than that based on the single photovoltaic effect. What's more, this device also has better DUV photoelectric properties when compared with Ag/Lu2O3/GaN detectors. These results indicate that the dual-field coupling effect induced by light in the Ti3C2Tx/Lu2O3 heterojunction is key to enhancing the detection performance of Lu2O3-based DUV PDs. This work provides new ideas for the application of Lu2O3 wide-bandgap semiconductors in high-performance DUV photodetectors. [ABSTRACT FROM AUTHOR]

The von Neumann bottleneck has long been a significant obstacle to the advancement of the era of intelligent computing. Neuromorphic devices are considered a promising solution to overcome this bottleneck. These devices draw inspiration from the information processing and computing capabilities of neurons in the human brain. Nevertheless, biomimetic synaptic devices used in neural network computing encounter significant challenges, including high nonlinearity in regulation, limited abundance of state conductance, and restrictions in unidirectional plasticity. Here, a memristor synaptic device is reported that utilizes the ion migration properties of MoTe2/MoS2−xOx heterojunction interface. This device demonstrates remarkable exceptional linearity, extensive dynamic regulation, and bidirectional independently controllable synaptic plasticity when subjected to bimodal regulation using electrical and optical signals. In addition, it shows significant paired‐pulse facilitation, empirical learning, and spike‐timing‐dependent properties. Furthermore, a deep learning framework is constructed to evaluate the reliability of devices in neuromorphic computation. The electronic synapses achieve high accuracy rates of 99.3% and 96.5% in recognizing digits and floral graphics, while photonic synapses achieve 95.3% and 91.5%. These findings emphasize the superior performance of photonic synapses in synaptic computation and provide a potential methodology for integrating multimodal neuromorphic hardware with artificial intelligence computing systems. [ABSTRACT FROM AUTHOR]

Enhancing the availability and reliability of dielectric ceramic energy storage devices is of great importance. In this work, (1- x) Na 0. 5 Bi 0. 5 TiO 3 – x Bi( Mg 0. 5 Hf 0. 5 ) O 3 (NBT– x BMH) lead-free ceramics were created utilizing a solid-state reaction technique. All NBT– x BMH ceramics have a single perovskite structure. With increasing BMH doping, the grain size shrinks drastically, which greatly enhances the breakdown electric field (310 kV/cm at x = 0.25). Additionally, the relaxation behaviors of NBT– x BMH ceramics with high BMH content are more remarkable. Among all designed components, the NBT–0.25BMH ceramic exhibits the best energy storage performance with a high W rec of 4.63 J/ cm 3 and an η of 75.1% at 310 kV/cm. The NBT–0.25BMH ceramic has exceptional resistance to fluctuations in both frequency (5–500 Hz) and temperature (30–100 ∘ C). Charge–discharge test shows that the NBT–0.25BMH ceramic has a quick discharge rate ( t 0. 9 < 110 ns). With these properties, the NBT–0.25BMH ceramic may have applications in microdevices as well as in ultra-high power electronic systems. [ABSTRACT FROM AUTHOR]

Based on the design from the view of the Goldschmidt tolerance factor, Ba0.955La0.03TiO3-doped Zr ferroelectric ceramics were prepared by solid-state reaction method. The experimental results show that our hypothesis does adjust the thermal stability Ba0.955La0.03TiO3 ferroelectric ceramics. The findings can be supported by the actual results of the following characterization methods. Room-temperature X-ray diffraction and field emission scanning microscopy demonstrate that the crystallization of these ceramics is good. The essential dielectric properties, electrical conductivity, impedance spectroscopy, and electrical modulus of ceramics were measured. Besides, impedance spectroscopy and electrical modulus spectrum indicated that the high-temperature dielectric relaxation behavior is related to the oxygen vacancies. [ABSTRACT FROM AUTHOR]

Ferroelectric materials with the typical perovskite structure are widely used in capacitors, ultrasonic devices, oil drilling, transducers, and other fields. Lead-lanthanum-zirconium-titanate ceramics co-doped with Sn and Ba, have been widely investigated. However, there is little attention has been focused on the dielectric properties of barium-lanthanum-zirconium-titanate. Thus, in this work, Sn doped Ba0.955La0.03Zr0.02Ti0.98O3 ferroelectric ceramics were prepared via a classical high-temperature solid state reaction. Scanning Electron Microscopy (SEM) was used to observe the surface appearance of ceramics. The X-ray diffraction (XRD) patterns at room temperature, indicate that the ceramics are well crystallized. Impedance properties and dielectric properties reflect the characteristic of typical high temperature dielectric relaxation behavior. The conductive activation energy and the relaxation activation energy are obtained through the calculation of the Arrhenius law. The fitting results show that the dielectric relaxation behavior at high-temperature, was related to the oxygen defect. The electrical modulus verified the partial short-range carrier migration, also contribute to the high-temperature dielectric properties. [ABSTRACT FROM AUTHOR]