Two-dimensional (2D) layered semiconductors have recently emerged as attractive building blocks for next-generation low-power nonvolatile memories. However, challenges remain in the controllable fabrication of bipolar resistive switching circuit components from these materials. Here, the experimental realization of lateral memtransistors from monolayer single-crystal molybdenum disulfide (MoS) utilizing a focused helium ion beam is reported. Site-specific irradiation with the focused probe of a helium ion microscope creates a nanometer-scale defect-rich region, bisecting the MoS lattice. The reversible drift of these defects in the applied electric field modulates the resistance of the channel, enabling versatile memristive functionality. The device can reliably retain its resistance ratios and set/reset biases for 1180 switching cycles. Long-term potentiation and depression with sharp habituation are demonstrated. This work establishes the feasibility of ion irradiation for controllable fabrication of 2D memristive devices with promising key performance parameters, such as low power consumption. The applicability of these devices for synaptic emulation may address the demands of future neuromorphic architectures.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1021/acsnano.9b07421 | DOI Listing |
Commun Phys
December 2024
LaserLaB, Department of Physics and Astronomy, Vrije Universiteit Amsterdam, De Boelelaan 1081, 1081 HV Amsterdam, the Netherlands.
Laser spectroscopy of atomic hydrogen and hydrogen-like atoms is a powerful tool for tests of fundamental physics. The 1-2 transition of hydrogen in particular is a cornerstone for stringent Quantum Electrodynamics (QED) tests and for an accurate determination of the Rydberg constant. We report laser excitation of the 1-2 transition in singly-ionized helium (He), a hydrogen-like ion with much higher sensitivity to QED than hydrogen itself.
View Article and Find Full Text PDFSmall
December 2024
School of Nuclear Science and Engineering, Shanghai Jiao Tong University, Shanghai, 200240, China.
Ultrathin polymer membranes on porous substrates exhibit excellent gas and ion permeability and have important applications in many fields, such as membrane separation and batteries. However, there is still a lack of facile and general methods for the direct preparation of ultrathin polymer membranes on porous substrates, especially from polymer solutions. Within this work, a new strategy to fabricate centimeter-size ultrathin polymer membranes (thickness down to 16 nm) is presented directly on porous supports by using the liquid-liquid interfacial spin-coating technique.
View Article and Find Full Text PDFNanomaterials (Basel)
December 2024
Electrochemistry Department, St. Petersburg State University, 7/9 Universitetskaya nab., St. Petersburg 199034, Russia.
In this work, a set of analytical techniques, including scanning electron microscopy (SEM), Raman scattering spectroscopy, X-ray photoelectron spectroscopy (XPS), energy-dispersive X-ray microanalysis (EDX) and cyclic voltammetry (CV), were used to study the impact of high-energy He ion irradiation on the structural and electrochemical characteristics of sulfur-containing multi-walled carbon nanotubes (S-MWCNTs) placed on a titanium substrate. The results indicate that the ion beam treatment of the S-MWCNT system led to an increase in the level of imperfections on the surface structures of the nanotubes due to the formation of point defects on their outer walls and the appearance of oxygen-containing functional groups, including SO groups, near these defects. At the same time, a significant increase in the sulfur concentration (by 6.
View Article and Find Full Text PDFTalanta
December 2024
State Key Laboratory of Geological Processes and Mineral Resources, China University of Geosciences, Wuhan, 430074, China. Electronic address:
Accurate in situ carbon isotopic measurements of magnesium-rich carbonates using LA-MC-ICP-MS require effective correction for isobaric interference, particularly from doubly charged Mg ions that can induce δC deviations of several permil. This study focuses on optimizing gas parameters and developing robust correction strategies to improve the accuracy of δC measurements. Experimental results demonstrate that the introduction of nitrogen gas at a flow rate of 4-6 mL/min effectively doubles signal sensitivity while optimizing low helium (0.
View Article and Find Full Text PDFPhys Med
December 2024
Australian Nuclear Science and Technology Organisation (ANSTO), Lucas Heights, Australia. Electronic address:
Purpose: To evaluate the impact of a range of shielding strategies on the rate of false positive detections by a simulated detector for application in Neutron Capture Enhanced Particle Therapy (NCEPT).
Methods: In this work, we extend a previously published method for neutron capture detection and discrimination. A Geant4 Monte Carlo model was designed, with the simulated irradiation of a poly(methyl methacrylate) phantom and cubic B insert with carbon and helium ion beams and various shielding configurations.
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!