Enhanced resistance switching in ultrathin Ag/SrTiO3/(La,Sr)MnO3 memristors and their long-term plasticity for neuromorphic computing

AbstractState-of-the-art memristors are mostly formed by vertical metal–insulator–metal (MIM) structure, which rely on the formation of conductive filaments for resistive switching (RS). However, owing to the stochastic formation of filament, the set/reset voltage of vertical MIM memristors is difficult to control, which results in poor temporal and spatial switching uniformity. Here, a two-terminal lateral memristor based on electron-beam-irradiated rhenium disulfide (ReS2) is realized, which unveils a resistive switching mechanism based on Schottky barrier height (SBH) modulation. The devices exhibit a forming-free, stable gradual RS characteristic, and simultaneously achieve a small transition voltage variation during positive and negative sweeps (6.3%/5.3%). The RS is attributed to the motion of sulfur vacancies induced by voltage bias in the device, which modulates the ReS2/metal SBH. The gradual SBH modulation stabilizes the temporal variation in contrast to the abrupt RS in MIM-based memristors. Moreover, the emulation of long-term synaptic plasticity of biological synapses is demonstrated using the device, manifesting its potential as artificial synapse for energy-efficient neuromorphic computing applications.

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Enhanced resistance switching stability of transparent ITO/TiO 2 /ITO sandwiches

Chinese Physics B ◽

10.1088/1674-1056/19/3/037304 ◽

2010 ◽

Vol 19 (3) ◽

pp. 037304 ◽

Cited By ~ 23

Author(s):

Meng Yang ◽

Zhang Pei-Jian ◽

Liu Zi-Yu ◽

Liao Zhao-Liang ◽

Pan Xin-Yu ◽

...

Keyword(s):

Resistance Switching ◽

Enhanced Resistance ◽

Switching Stability

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Reciprocating versus Rotary instruments: a review

Revista Odonto Ciência ◽

10.15448/1980-6523.2016.3.20917 ◽

2016 ◽

Vol 31 (3) ◽

pp. 135

Author(s):

Flavia Villela Laurindo ◽

José Antonio Poli de Figueiredo

Keyword(s):

New Era ◽

Enhanced Resistance ◽

Rotary Instruments ◽

Continuous Rotation ◽

Rotational Systems ◽

Reciprocating Instruments ◽

Single Use ◽

Reciprocating Systems

Objective: Literature started to point out essential parameters involving reciprocating instruments through clinical and laboratory essays. Looking into apical debris extrusion, incidence of instrument breakage, canal centering ability, apical zipping, a myriad of information has become available. The aim of this review is to revisit the literature and compare reciprocal and continuous rotation techniques.Methods: A review of current literature may collect recent findings.Conclusion: Reciprocating systems are similar in some aspects in comparison to rotational systems, with regards to cleaning ability, centered preparations, cleaning ability, reduction of Enterococcus faecalis and dentine defects. On the other hand, being single use and enhanced resistance to fatigue, together with novel methods to treat the alloy may lead to the thought that reciprocal systems are an excellent aid to root canal preparation. However, more needs to be understood about this new era of instruments to verify, long term and especially in vivo, the success and failure when these instruments are used.

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Oxidative Stress Induction of the MexXY Multidrug Efflux Genes and Promotion of Aminoglycoside Resistance Development inPseudomonas aeruginosa

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.01495-10 ◽

2010 ◽

Vol 55 (3) ◽

pp. 1068-1074 ◽

Cited By ~ 65

Author(s):

Sebastien Fraud ◽

Keith Poole

Keyword(s):

Multidrug Efflux ◽

Efflux System ◽

Aminoglycoside Resistance ◽

Resistance Development ◽

Enhanced Resistance ◽

Resistant Mutants ◽

Multidrug Efflux System

ABSTRACTExposure to reactive oxygen species (ROS) (e.g., peroxide) was shown to induce expression of the PA5471 gene, which was previously shown to be required for antimicrobial induction of the MexXY components of the MexXY-OprM multidrug efflux system and aminoglycoside resistance determinant inPseudomonas aeruginosa. mexXYwas also induced by peroxide exposure, and this too was PA5471 dependent. The prospect of ROS promotingmexXYexpression and aminoglycoside resistance recallsP. aeruginosainfection of the chronically inflamed lungs of cystic fibrosis (CF) patients, where the organism is exposed to ROS and where MexXY-OprM predominates as the mechanism of aminoglycoside resistance. While ROS did not enhance aminoglycoside resistancein vitro, long-term (8-day) exposure ofP. aeruginosato peroxide (mimicking chronicin vivoROS exposure) increased aminoglycoside resistance frequency, dependent upon PA5471 andmexXY. This enhanced resistance frequency was also seen in a mutant strain overexpressing PA5471, in the absence of peroxide, suggesting that induction of PA5471 by peroxide was key to peroxide enhancement of aminoglycoside resistance frequency. Resistant mutants selected following peroxide exposure were typically pan-aminoglycoside-resistant, withmexXYgenerally required for this resistance. Moreover, PA5471 was required formexXYexpression and aminoglycoside resistance in these as well as several CF isolates examined.

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A Variable Resistor Micro System Based on Electro-Explosion

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.645-646.865 ◽

2015 ◽

Vol 645-646 ◽

pp. 865-868

Author(s):

Xu Ran Ding ◽

Ya Bin Wang ◽

Wen Zhong Lou ◽

Yun Long Guo

Keyword(s):

Voltage Pulse ◽

Performance Test ◽

Resistance Switching ◽

Harsh Environments ◽

External Signal ◽

Test Results ◽

Variable Resistor

A novel type of variable resistor micro system based on electro-explosion is described and its performance test results are presented. The variable resistor consists of four metallic leads in parallel with different width and length thus different resistances and four one-time shot MEMS solid on-off switches. By killing off the metallic lines, the variable resistor varies its resistance. Switching is accomplished by a voltage pulse. The resistor can be driven by external signal and its predicted lifetime is very long. Besides, the resistor has no movable parts, therefore the resistor can be used for long term store systems and harsh environments.

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A Floating Gate Memory with U-Shape Recessed Channel for Neuromorphic Computing and MCU Applications

Micromachines ◽

10.3390/mi10090558 ◽

2019 ◽

Vol 10 (9) ◽

pp. 558 ◽

Cited By ~ 2

Author(s):

Lu-Rong Gan ◽

Ya-Rong Wang ◽

Lin Chen ◽

Hao Zhu ◽

Qing-Qing Sun

Keyword(s):

Long Term Potentiation ◽

Floating Gate ◽

Neuromorphic Computing ◽

Term Potentiation ◽

Floating Gate Memory ◽

High K Dielectric ◽

Recessed Channel ◽

And Control ◽

Micro Controller Unit

We have simulated a U-shape recessed channel floating gate memory by Sentaurus TCAD tools. Since the floating gate (FG) is vertically placed between source (S) and drain (D), and control gate (CG) and HfO2 high-k dielectric extend above source and drain, the integrated density can be well improved, while the erasing and programming speed of the device are respectively decreased to 75 ns and 50 ns. In addition, comprehensive synaptic abilities including long-term potentiation (LTP) and long-term depression (LTD) are demonstrated in our U-shape recessed channel FG memory, highly resembling the biological synapses. These simulation results show that our device has the potential to be well used as embedded memory in neuromorphic computing and MCU (Micro Controller Unit) applications.

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An Organic Flexible Artificial Bio-Synapses with Long-Term Plasticity for Neuromorphic Computing

Micromachines ◽

10.3390/mi9050239 ◽

2018 ◽

Vol 9 (5) ◽

pp. 239 ◽

Cited By ~ 7

Author(s):

Tian-Yu Wang ◽

Zhen-Yu He ◽

Lin Chen ◽

Hao Zhu ◽

Qing-Qing Sun ◽

...

Keyword(s):

Neuromorphic Computing

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ReSe2-Based RRAM and Circuit-Level Model for Neuromorphic Computing

Frontiers in Nanotechnology ◽

10.3389/fnano.2021.782836 ◽

2021 ◽

Vol 3 ◽

Author(s):

Yifu Huang ◽

Yuqian Gu ◽

Xiaohan Wu ◽

Ruijing Ge ◽

Yao-Feng Chang ◽

...

Keyword(s):

Data Storage ◽

Resistive Switching ◽

Random Access ◽

Long Term Potentiation ◽

Computing System ◽

Switching Behavior ◽

Active Layer Thickness ◽

Neuromorphic Computing ◽

Multiple Step

Resistive random-access memory (RRAM) devices have drawn increasing interest for the simplicity of its structure, low power consumption and applicability to neuromorphic computing. By combining analog computing and data storage at the device level, neuromorphic computing system has the potential to meet the demand of computing power in applications such as artificial intelligence (AI), machine learning (ML) and Internet of Things (IoT). Monolayer rhenium diselenide (ReSe2), as a two-dimensional (2D) material, has been reported to exhibit non-volatile resistive switching (NVRS) behavior in RRAM devices with sub-nanometer active layer thickness. In this paper, we demonstrate stable multiple-step RESET in ReSe2 RRAM devices by applying different levels of DC electrical bias. Pulse measurement has been conducted to study the neuromorphic characteristics. Under different height of stimuli, the ReSe2 RRAM devices have been found to switch to different resistance states, which shows the potentiation of synaptic applications. Long-term potentiation (LTP) and depression (LTD) have been demonstrated with the gradual resistance switching behaviors observed in long-term plasticity programming. A Verilog-A model is proposed based on the multiple-step resistive switching behavior. By implementing the LTP/LTD parameters, an artificial neural network (ANN) is constructed for the demonstration of handwriting classification using Modified National Institute of Standards and Technology (MNIST) dataset.

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