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The integration of chiral elements within a multiple resonance (MR) motif affords a prospective avenue to construct satisfying emitters tailored for state‐of‐the‐art circularly polarized organic light–emitting diodes (CP‐OLEDs). However, the concurrently realizing of both high luminescence efficiency and favorable dissymmetry factors (gPL) still remains a formidable challenge, particularly when aligning with the requirement of high color purity. Herein, a dual‐pronged approach is proposed to reconcile such trade‐offs by directly fusing a secondary chiral donor onto the MR scaffold, thereby facilitating a hybrid short/long‐range charge‐transfer with fine‐tuned compositions. Theoretical calculations unveil the pronounced impact of the chiral donor on meticulously refining the characteristics of excited states, therefore yielding a considerable gPL of 3.3 × 10−3, along with a high fluorescence quantum yield of 0.97, and a rapid reverse intersystem crossing rate of 3.06 × 105 s−1 in one embodiment. Leveraging these merits, electroluminescence devices incorporating them as chiral dopants exhibit exceptional performance, showcasing a peak external quantum efficiency of 36.6% and remarkable Commission Internationale de L'Eclairage coordinates of (0.19, 0.71), which represent one of the most notable achievements among pure‐green CP‐OLEDs. [ABSTRACT FROM AUTHOR]

While spin–orbit torque (SOT) devices are extensively investigated due to their potential for use in neural network computation, it remains challenging to explore the hardware for neural networks. In this paper, the field‐free memristive SOT switching of the CoPt single layer is used to propose a neuromorphic hardware circuit for detecting edges in images. Owing to its threefold symmetry of inversion, the polarity of SOT switching can be reversed by rotating the current by 60°. Moreover, the process of current‐induced SOT switching exhibits stable multi‐state magnetic switching behavior, and can be controllably tuned by using the pulse of the current. As the slope of the applied ramp pulse current increased, the wave of the anomalous Hall resistance changed from a curve with normally memristive property to trigonometric, and finally to cosine. The design of the hardware circuit for a single SOT device is subsequently formulated to detect the edges in images. The results of experiments verified the capability of this device to detect the edge lines in images with high accuracy, which confirms its potential for use in the hardware of neuromorphic computing platforms. The work here provides guidance for the application of SOT‐based devices to neuromorphic hardware. [ABSTRACT FROM AUTHOR]

Substrates are crucial to the growth of organic semiconductor thin films and crystals, and thus the performance of the organic field‐effect transistors. To date, there has been no single substrate that can fulfill the demand for low‐voltage operation, large‐area crystal growth, bias stress stability, and mechanical flexibility at the same time. Here, a novel transfer method is reported, which separates the growth of the organic semiconductor active layers and the rest of the fabrication steps of the field‐effect transistors, so that high‐mobility active layers and bias‐stable dielectric substrates are combined. With the proposed transfer method, both vacuum sublimated thin films and solution‐processed crystals show remarkable improvement in the bias stability. With the high‐k dielectric and ultraflexible substrate, the device can operate at 2 V and shows no degradation in the carrier mobility when the bending radius is down to 215 mm. It is believed that this transfer method can advance the fabrication techniques of high‐performance organic field‐effect transistors, especially for their conformal or ultraflexible applications. [ABSTRACT FROM AUTHOR]

Surface‐enhanced Raman scattering (SERS) has been extensively studied, but quantifiable results on electromagnetic enhancement (EM) are primarily focused on noble metals; as for metal oxides, limited studies exist, and a common impression regarding Raman scatterings is not able to elaborate mechanisms involving EM and multiplicative chemical enhancements. Leveraging on the shape‐controlled synthesis of Cu2O, the hexagonal nanoplates exhibit a remarkable SERS activity and reproducible measurements, enabling a systematic investigation of the SERS mechanism of Cu2O. Here the shape‐dependent SERS activity is elaborated by applying finite‐difference time‐domain simulation; the dominant contributions to SERS activity ascribed to chemical‐bonding and charge‐transfer (CT) enhancements are investigated using ab initio calculation. As the example, it is shown that the chemisorption of 4‐aminothiophenol (PATP) on Cu2O nanoplates leads to the shift of highest occupied molecular orbital and lowest unoccupied molecular orbital levels, promoting efficient CT processes. The vibronic coupling of the conduction and valence bands of Cu2O with the molecular orbital of PATP further enhances the Raman scattering. This study on the combined EM and CT channels on Cu2O nanoplates is promising to identify a new group of SERS‐active substrates and advance the fundamental understanding of SERS mechanism, which also opens up a prospect of biocompatible and in situ diagnosis. [ABSTRACT FROM AUTHOR]