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Abstract Although many substorm‐related observations have been made, we still have limited insight into propagation of the plasma and field perturbations in Pi2 frequencies (∼7–25 mHz) in association with substorm aurora, particularly from the auroral source region in the inner magnetosphere to the ground. In this study, we present conjugate observations of a substorm brightening aurora using an all‐sky camera and an inner‐magnetospheric satellite Arase atL ∼ 5. A camera at Gakona (62.39°N, 214.78°E), Alaska, observed a substorm auroral brightening on 28 December 2018, and the footprint of the satellite was located just equatorward of the aurora. Around the timing of the auroral brightening, the satellite observed a series of quasi‐periodic variations in the electric and magnetic fields and in the energy flux of electrons and ions. We demonstrate that the diamagnetic variations of thermal pressure and medium‐energy ion energy flux in the inner magnetosphere show approximately one‐to‐one correspondence with the oscillations in luminosity of the substorm brightening aurora and high‐latitudinal Pi2 pulsations on the ground. We also found their anti‐correlation with low‐energy electrons. Cavity‐type Pi2 pulsations were observed at mid‐ and low‐latitudinal stations. Based on these observations, we suggest that a wave phenomenon in the substorm auroral source region, like ballooning type instability, play an important role in the development of substorm and related auroral brightening and high‐latitude Pi2, and that the variation of the auroral luminosity was directly driven by keV electrons which were modulated by Alfven waves in the inner magnetosphere. 

Organic thin-film transistors (OTFTs) are drawing increasing attention due to their unique advantages of mechanical flexibility, low-cost fabrication, and biodegradability, enabling diverse applications that were not achievable using traditional inorganic transistors. With a growing number of complex applications being proposed, the need for expediting the design process and ensuring the yield of large-scale designs with organic technology increases. A complete digital standard cell library plays a crucial role in integrating the emerging organic technology into existing computer-aided-design (CAD) flows. In this paper, we present the design, fabrication, and characterization of a standard cell library based on bottom gate, top contact pentacene OTFTs. We also propose a commercial tool compatible, RTL-to-GDS flow along with a new organic process design kit (PDK) developed based on our process. To the best of our knowledge, this is the first open-source organic standard cell library, enabling the community to explore this emerging technology. 

The suppression of leakage current via surface passivation plays a critical role for GaSb‐based optoelectronic devices. In this Letter the authors carefully optimise the sulfur passivation parameters for improving the performance of GaSb p–i–n devices. Two competing processes are evaluated during the sulfur passivation process: the hydrolysis of HS^–ions that aide surface passivation and the re‐oxidation, respectively. Upon the optimisation of sulfur passivation parameters and subsequent encapsulation with atomic layer deposition Al₂O₃, the surface resistivity significantly increased from 4.3 kΩ.cm to 28.6 kΩ.cm, leading to a 19.1 times drop in dark current at room temperature for the GaSb p–i–n structure. This Letter provides a repeatable and stable passivation approach for improving the optoelectronic performance of GaSb‐based devices.