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Neuromorphic computing aims to leverage physical phenomena of adaptive materials for emulating information processing capabilities and effectiveness of biological neuronal circuits. In this framework, memristors (resistors with memory) based on 2D materials are demonstrated for the hardware implementation of highly integrated artificial neural networks. All the works reported thus far exploited electrical properties of 2D materials to emulate neuromorphic functionalities. Here, a 2D memitter (emitter with memory) is reported on that exploits the stimuli‐responsive photoluminescence of a monolayer WS2 for neuromorphic‐type of data processing. A combined experimental and modeling approach reveals that photoluminescent dynamics triggered by optical stimulation emulates Short‐Term synaptic Plasticity and Visual Short‐Term Memory typical of biological systems. While spatio‐temporal processing capabilities of input signals can be used for information processing in the context of reservoir computing, the capability of the 2D memitter of sensing, processing, and memorizing‐forgetting optical inputs in the same physical substrate can be utilized for in‐sensor computing. [ABSTRACT FROM AUTHOR]

Neuromorphic 2D Memitter In article number 2403158, Federico Ferrarese Lupi, GianlucaMilano, Carlo Grazianetti, and co‐workers describes the concept of 2D memitter, which exploits the stimuli‐responsive photoluminescence of a monolayer WS2 for neuromorphic‐type of data processing. [ABSTRACT FROM AUTHOR]

Hyperbolic metamaterials (HMMs) offer unconventional properties in the field of optics, enabling opportunities for confinement and propagation of light at the nanoscale. In‐plane orientation of the optical axis, in the direction coinciding with the anisotropy of the HMMs, is desirable for a variety of novel applications in nanophotonics and imaging. Here, a method for creating localized HMMs with in‐plane optical axis, based on block copolymer (BCP) blend instability, is introduced. The dewetting of BCP thin film over topographically defined substrates generates droplets composed of highly ordered lamellar nanostructures in hierarchical configuration. The hierarchical nanostructures represent a valuable platform for the subsequent pattern transfer into a Au/air HMM, exhibiting hyperbolic behavior in a broad wavelength range in the visible spectrum. A computed Purcell factor as high as 32 at 580 nm supports the strong reduction in the fluorescence lifetime of defects in nanodiamonds placed on top of the HMM. [ABSTRACT FROM AUTHOR]

As a consequence of the redefinition of the International System of Units (SI), where units are defined in terms of fundamental physical constants, memristive devices represent a promising platform for quantum metrology. Coupling ionics with electronics, memristive devices can exhibit conductance levels quantized in multiples of the fundamental quantum of conductance G0= 2e2/h. Since the fundamental quantum of conductance G0 is related only to physical constants that assume fixed value in the revised SI, memristive devices can be exploited for the practical realization of a quantum‐based resistance standard that, differently from quantum‐Hall based devices conventionally adopted as resistance standards, can operate in different ambient conditions (air, vacuum, harsh environment), in a wide range of temperatures and without the need of an applied magnetic field. In this work, the possibility of using memristive devices for quantum metrology is critically discussed, based on recent experimental and theoretical advances on quantum conductance phenomena reported in literature. Thanks to the high operational speed, high scalability down to the nanometer scale, and CMOS compatibility, memristive devices allow on‐chip implementation of a resistance standard required for the realization of self‐calibrating electrical systems and equipment with zero‐chain traceability in accordance with the revised SI. [ABSTRACT FROM AUTHOR]

The continuous and aggressive scaling in semiconductor technology results in the integration of increasingly complex 3D architectures and new materials. The realization of these downscaled 3D structures requires also further improvement in 3D characterization techniques. In this work, a potential route to improve the accuracy and reliability of the quantitative analysis of 3D nano‐devices is investigated. 3D organic and inorganic reference nanostructures with dimensions and structural ordering resembling those utilized in industrial applications are fabricated and characterized in detail. The 3D organic nanostructures are fabricated exploiting the self‐assembly capability of di‐block copolymers. Subsequent deposition of a thin Al film lead to the formation and realization of nanostructured Al. In addition, different inorganic nanostructures are fabricated using electron beam lithography. The various nanostructures are characterized with respect to their dimensions as well as composition using various analytical techniques namely reference‐free grazing incidence X‐ray fluorescence, grazing incidence small angle X‐ray scattering, scanning electron microscopy, and spectroscopic ellipsometry. [ABSTRACT FROM AUTHOR]

Hydroxyl terminated poly(styrene- r-methyl methacrylate) (P(S- r- MMA)) random copolymers ( RCPs), with molecular weight ( Mn) spanning from 1700 to 69 000 g mol−1 and equal styrene unit content, were grafted at different temperatures onto a silicon oxide surface and subsequently used to study the orientation of nanodomains with respect to the substrate, in cylinder forming polystyrene- b-poly(methyl methacrylate) ( PS- b- PMMA) block copolymer thin films. When the grafting temperature increases from 250 to 310 °C, a substantial increase in the grafting rate is observed. In addition, an increase in the surface neutralization efficiency occurs thus resulting in an increase in the robustness of the surface neutralization step. These data revealed that the neutralization of the substrate is the result of a complex interplay between RCP film characteristics and underlying substrate properties that can be finely tuned by properly adjusting the temperature of the grafting process. © 2016 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

The cover image, by Katia Sparnacci et al., is based on the Research Article High temperature surface neutralization process with random copolymers for block copolymer self-assembly, DOI: . [ABSTRACT FROM AUTHOR]