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Mid-infrared (MIR) radiation is essential for remote gas sensing, ranging, and lidar applications, where high pulse energy and narrow linewidth are the keys to the high sensitivity over long distance. However, complex optical and electronic locking schemes are normally required to achieve both features at the same time. Here, we demonstrate pulse-pumped single-longitudinal-mode (SLM) MIR generation using a microresonator seed in the form of a sheet optical parametric oscillator (SOPO). The SOPO features a sub-coherence-length thickness of 400 µm, which enables SLM and high-energy oscillation using cavity phase matching. Its output around 1.55 µm is seeded into an optical parametric amplifier and locks the MIR output in SLM at 3.38 µm. In a simple and compact setup, up to 21% conversion efficiency and 22% slope efficiency are measured with a MIR output energy of 54 µJ. This SLM MIR source with the SOPO seed greatly reduces the system size and is compatible for further integration for field-deployable devices and thus has broad applications in the field of remote gas sensing. [ABSTRACT FROM AUTHOR]

Aims Accumulating evidence supports the indispensable role of protein arginine methyltransferase 5 (PRMT5) in the pathological progression of several human cancers. As an important enzyme-regulating protein methylation, how PRMT5 participates in vascular remodelling remains unknown. The aim of this study was to investigate the role and underlying mechanism of PRMT5 in neointimal formation and to evaluate its potential as an effective therapeutic target for the condition. Methods and results Aberrant PRMT5 overexpression was positively correlated with clinical carotid arterial stenosis. Vascular smooth muscle cell (SMC)-specific PRMT5 knockout inhibited intimal hyperplasia with an enhanced expression of contractile markers in mice. Conversely, PRMT5 overexpression inhibited SMC contractile markers and promoted intimal hyperplasia. Furthermore, we showed that PRMT5 promoted SMC phenotypic switching by stabilizing Kruppel-like factor 4 (KLF4). Mechanistically, PRMT5-mediated KLF4 methylation inhibited ubiquitin-dependent proteolysis of KLF4, leading to a disruption of myocardin (MYOCD)–serum response factor (SRF) interaction and MYOCD–SRF-mediated the transcription of SMC contractile markers. Conclusion Our data demonstrated that PRMT5 critically mediated vascular remodelling by promoting KLF4-mediated SMC phenotypic conversion and consequently the progression of intimal hyperplasia. Therefore, PRMT5 may represent a potential therapeutic target for intimal hyperplasia–associated vascular diseases. [ABSTRACT FROM AUTHOR]

The effect of ion-induced defects on graphene was studied to investigate the contact resistance of 40 nm palladium (Pd) contacting on graphene. The defect development was considered and analyzed by irradiating boron (B), carbon (C), nitrogen (N2), and argon (Ar) ions on as-transferred graphene before metallization. The bombardment energy was set at 1.5 keV and ion dose at 1 × 1014 ions/cm2. The defect yields under different ion irradiation conditions were examined by Raman spectroscopy. Although, dissolution process occurs spontaneously upon metal deposition, chemical reaction between metal and graphene is more pronounced at higher temperatures. The rapid thermal annealing (RTA) treatment was performed to improve the Pd/graphene contact after annealing at 450 °C, 500 °C, 550 °C, and 600 °C. The lowest contact resistance of 95.2 Ω-µm was achieved at 550 °C RTA with Ar ion irradiation. We have proved that ion irradiation significantly enhance the Pd/graphene contact instead of pd/pristine graphene contact. Therefore, in view of the contention of results ion induced defects before metallization plus the RTA served an excellent purpose to reduce the contact resistance. [ABSTRACT FROM AUTHOR]

Periodically poled lithium niobate on insulator (PPLNOI) offers an admirably promising platform for the advancement of nonlinear photonic integrated circuits (PICs). In this context, domain inversion engineering emerges as a key process to achieve efficient nonlinear conversion. However, periodic poling processing of thin-film lithium niobate has only been realized on the chip level, which significantly limits its applications in large-scale nonlinear photonic systems that necessitate the integration of multiple nonlinear components on a single chip with uniform performances. Here, we demonstrate a wafer-scale periodic poling technique on a 4-inch LNOI wafer with high fidelity. The reversal lengths span from 0.5 to 10.17 mm, encompassing an area of ~1 cm2 with periods ranging from 4.38 to 5.51 μm. Efficient poling was achieved with a single manipulation, benefiting from the targeted grouped electrode pads and adaptable comb line widths in our experiment. As a result, domain inversion is ultimately implemented across the entire wafer with a 100% success rate and 98% high-quality rate on average, showcasing high throughput and stability, which is fundamentally scalable and highly cost-effective in contrast to traditional size-restricted chiplet-level poling. Our study holds significant promise to dramatically promote ultra-high performance to a broad spectrum of applications, including optical communications, photonic neural networks, and quantum photonics. [ABSTRACT FROM AUTHOR]

The degradation of InSe film and its impact on field effect transistors are investigated. After the exposure to atmospheric environment, 2D InSe flakes produce irreversible degradation that cannot be stopped by the passivation layer of h-BN, causing a rapid decrease for InSe FETs performance, which is attributed to the large number of traps formed by the oxidation of 2D InSe and adsorption to impurities. The residual photoresist in lithography can cause unwanted doping to the material and reduce the performance of the device. To avoid contamination, a high-performance InSe FET is achieved by a using hard shadow mask instead of the lithography process. The high-quality channel surface is manifested by the hysteresis of the transfer characteristic curve. The hysteresis of InSe FET is less than 0.1 V at Vd of 0.2, 0.5, and 1 V. And a high on/off ratio of 1.25 × 108 is achieved, as well relative high Ion of 1.98 × 10−4 A and low SS of 70.4 mV/dec at Vd = 1 V are obtained, demonstrating the potential for InSe high-performance logic device. [ABSTRACT FROM AUTHOR]

A multivalued logic (MVL) device can achieve greater data density with a smaller footprint than a traditional binary logic device. In this study, a ternary logic inverter based on negative capacitance FETs (NCFETs) without additional footprints has been realized. By enhancing the amplification in surface potential owing to the utilization of the negative capacitance, the third intermediate state can be successfully obtained at VDD/2 in the conventional binary CMOS inverter. The third intermediate state arises due to no-saturation effect of drain current, and the noise margin of the third intermediate state (NMM) can be optimized by changing ferroelectric thickness or annealing temperature of ferroelectric material. The influence of remnant polarization (Pr) and coercive electric (EC) variation on the ternary logic inverter was investigated based on experimental data. Moreover, a ternary logic 8T SRAM with transmission gate logic (TGL) was proposed, and the results show that the proposed 8T SRAM cell exhibits nondestructive read and reliable write operations for all three states. [ABSTRACT FROM AUTHOR]

Summary: Strigolactones (SLs), a class of the most recently identified terpenoid phytohormones, play essential roles in plant development, specifically in suppressing shoot branching. MAX2, a subunit of an SCF E3 ligase and a positive regulator that inhibits shoot branching, is likely a key SL signaling component. Here, we provide genetic and biochemical evidence to demonstrate that BES1 interacts with MAX2 and acts as its substrate to regulate SL-responsive gene expression. Additional AtD14, a putative receptor of SLs, can promote BES1 degradation. Knockdown of BES1 and its homologs dramatically suppressed the branching phenotype of max2-1 mutant. These results portray an SL signaling cascade from the putative receptor to downstream transcription factors. In addition, we demonstrate that the SL and brassinosteroid (BR) signaling pathways distinctly regulate the same transcription factor, BES1, to control specific developmental processes. [Copyright &y& Elsevier]

The applications of a boron-doped diamond (BDD) used in electrode application for toxic and refractory organic degradation have attracted much attention, and its efficiency is considered to be an important factor for its practical application. In this study, BDD thin films were prepared on Ti plates by double bias-assisted hot filament chemical vapor deposition (HFCVD) technique. A reactive ion etching process was introduced by a positive grid bias and a negative substrate bias which can generate an electric field in HFCVD system. Then a novel structure of BDD electrode with nanocone arrays was successfully etched from a flat diamond thin film by this system. The addition of the bias greatly improved the etching efficiency and promoted the formation of nanocones structures. The cyclic voltammograms (CV) test showed nanostructured BDD (NBDD) electrodes had excellent electrochemical performance almost the same as that of the electrodes with untreated surfaces. It had a large effective electroactive surface area (EASA), which was 31.0% greater than the unetched electrode. As a result, the NBDD electrode exhibited improved electrocatalytic performance as compared with the untreated one, i.e., an about 24.3% increase of chemical oxygen demand (COD) removal efficiency. Among them, the superiority of NBDD electrode was obvious in the initial stage due to its highest concentration in the initial stage. In addition, the NBDD electrode achieved higher average current efficiency (ACE) as compared with the untreated one. Unlabelled Image • The BDD nanostructure was prepared by double bias-assisted HFCVD system. • The NBDD films were used as electrodes for wastewater treatment. • The EASA of the NBDD electrodes was increased. • The COD removal rate and ACE of NBDD electrodes were improved. [ABSTRACT FROM AUTHOR]

With the development of new designs and materials for nano-scale transistors, vertical Gate-All-Around Field Effect Transistors (vGAAFETs) with germanium as channel materials have emerged as excellent choices. The driving forces for this choice are the full control of the short channel effect and the high carrier mobility in the channel region. In this work, a novel process to form the structure for a VGAA transistor with a Ge channel is presented. The structure consists of multilayers of Si0.2Ge0.8/Ge grown on a Ge buffer layer grown by the reduced pressure chemical vapor deposition technique. The Ge buffer layer growth consists of low-temperature growth at 400 °C and high-temperature growth at 650 °C. The impact of the epitaxial quality of the Ge buffer on the defect density in the Si0.2Ge0.8/Ge stack has been studied. In this part, different thicknesses (0.6, 1.2 and 2.0 µm) of the Ge buffer on the quality of the Si0.2Ge0.8/Ge stack structure have been investigated. The thicker Ge buffer layer can improve surface roughness. A high-quality and atomically smooth surface with RMS 0.73 nm of the Si0.2Ge0.8/Ge stack structure can be successfully realized on the 1.2 µm Ge buffer layer. After the epitaxy step, the multilayer is vertically dry-etched to form a fin where the Ge channel is selectively released to SiGe by using wet-etching in HNO3 and H2O2 solution at room temperature. It has been found that the solution concentration has a great effect on the etch rate. The relative etching depth of Ge is linearly dependent on the etching time in H2O2 solution. The results of this study emphasize the selective etching of germanium and provide the experimental basis for the release of germanium channels in the future. [ABSTRACT FROM AUTHOR]