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A number of synapse devices have been intensively studied for the neuromorphic system which is the next-generation energy-efficient computing method. Among these various types of synapse devices, photonic synapse devices recently attracted significant attention. In particular, the photonic synapse devices using persistent photoconductivity (PPC) phenomena in oxide semiconductors are receiving much attention due to the similarity between relaxation characteristics of PPC phenomena and Ca2+ dynamics of biological synapses. However, these devices have limitations in its controllability of the relaxation characteristics of PPC behaviors. To utilize the oxide semiconductor as photonic synapse devices, relaxation behavior needs to be accurately controlled. In this study, a photonic synapse device with controlled relaxation characteristics by using an oxide semiconductor and a ferroelectric layer is demonstrated. This device exploits the PPC characteristics to demonstrate synaptic functions including short-term plasticity, paired-pulse facilitation (PPF), and long-term plasticity (LTP). The relaxation properties are controlled by the polarization of the ferroelectric layer, and this polarization is used to control the amount by which the conductance levels increase during PPF operation and to enhance LTP characteristics. This study provides an important step toward the development of photonic synapses with tunable synaptic functions. 相似文献
63.
Yuhang Sun Junkyu Kim Neel Chatterjee Sarah L. Swisher 《Advanced Electronic Materials》2021,7(5):2001037
In metal-oxide thin-film transistors (TFTs), high-k gate dielectrics often yield a higher electron mobility than SiO2. However, investigations regarding the mechanism of this high-k “mobility boost” are relatively scarce. To explore this phenomenon, solution-processed In2O3 TFTs are fabricated using eight different gate dielectrics (SiO2, Al2O3, ZrO2, HfO2, and bilayer SiO2/high-k structures). With these structures, the total gate capacitance can be varied independently from the semiconductor–dielectric interface to study this mobility enhancement. It is shown that the mobility enhancement is a combination of the effects of areal gate capacitance and interface quality for disordered oxide semiconductor devices. The ZrO2-gated TFTs achieve the highest mobility by inducing more accumulation charge with higher gate capacitance. Surprisingly, however, when the gate capacitance is held constant, no mobility enhancement is observed with the high-k gate dielectrics compared to SiO2. 相似文献
64.
So-Young Kim Kiyung Kim A. Reum Kim Ho-In Lee Yongsu Lee Seung-Mo Kim Sung Ho Yu Hae-Won Lee Hyeon Jun Hwang Myung Mo Sung Byoung Hun Lee 《Advanced Electronic Materials》2021,7(6):2100247
For many decades, novel devices demonstrating step-wise current–voltage characteristic at room temperature have been pursued to realize multi-valued logic computing that has significant advantages such as extremely low power consumption and high-density information-processing capability. Recently, a novel ternary logic transistor has been constructed using an ultrathin ZnO/Al2O3-AlDMP/ZnO channel exhibiting a mobility edge-quantized conduction for the intermediate current level. This study investigates the operation principle of the ternary device using ZnO/Al2O3-AlDMP/ZnO stack and concludes that the first ZnO layer controls the level of the intermediate current, while the second ZnO layer controls the threshold voltage of the ternary device. These controllable electrical properties of the intermediate state of the ternary device have been applied to an n-type resistive-load standard ternary inverter, demonstrating the feasibility to achieve a ternary logic circuit consuming extremely low power with an optimal noise margin. 相似文献
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介绍了天荒坪抽水蓄能电站１号发电电动机（３００ＭＷ）推力轴承和导轴承的技术特点,分析了轴承润滑油回路的工作特点和方式,叙述了造成实际运行中轴承油温偏高的主要原因,简要评估了ＧＥ推力轴承和导轴承的设计优缺点。 相似文献
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《Ceramics International》2022,48(7):9083-9089
Direct-methane solid oxide fuel cells (DMSOFCs) have recently attracted substantial attention due to their simplified system, reduced cost, and the direct availability of methane fuel obtained from natural gas. Among oxygen-ion conductive materials, doped-ceria such as gadolinium-doped ceria (GDC) or samarium-doped ceria can be incorporated into Ni-based anodes to reinforce their coking resistance, enlarge their electrochemical reaction area, and improve the kinetics of the internal reforming/electrochemical oxidation of methane. To reduce the range of operating temperatures of DMSOFCs while maintaining their performance, the thin film deposition technique of magnetron sputtering was adopted in this work. An Ni-GDC thin-film anode and a Pt thin-film cathode were deposited on scandia-stabilized zirconia (ScSZ) electrolyte supports. This fuel cell was tested with directly supplied methane fuel (3% H2O) at 500 °C. The results demonstrated the effects of the GDC volume fraction in the anode—which was controlled by co-sputtering power—on open circuit voltage and electrochemical performance. The co-sputtered Ni-GDC anode was able to survive through 36-h operation, although there was some performance degradation. Field-emission scanning electron microscopy results revealed no formation of filamentous carbon on the Ni catalysts, despite the fact that both X-ray photoelectron spectroscopy and Raman spectroscopy analyses detected carbon coking. The relatively high performance and resistance to carbon coking of co-sputtered thin-film anode were attributed to its intrinsic small grain size. 相似文献
70.
我国废润滑油再生行业的现状及发展前景 总被引：3，自引：0，他引：3
调查了废润滑油再生处理的主要方式和环境因素,对国内废润滑油再生行业的政策法规状况进行了总结,对国内废润滑油再生行业的发展前景进行了展望,同时为我国废润滑油再生行业的正规化、专业化和规模化发展之路提出了建议。 相似文献