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La-doped BaSnO3 (BLSO) exhibits promising applications in oxide electronic devices, owing to its high electron mobility and good thermal stability. The introduction of extrinsic La dopants could actively interact with the formation of intrinsic oxygen vacancies in BLSO films, which collectively influence the resulting transport behavior. However, it is not clear which factor plays a dominant role when the La dopant ratio varies. Here, we fabricate BLSO films at lightly doped (0.2%) and heavily doped (7%) regimes and perform a systematic investigation on the oxygen vacancy impact on structure, optical, and transport properties of these BLSO films. It is revealed that the BLSO films grown at an ozone environment show larger strain and lower oxygen vacancy concentrations for all investigated dopant ratios. More importantly, the introduction of ozone decreases the mobility and the carrier concentration of both lightly doped and heavily doped films. This study reveals that the presence of oxygen vacancies enhances the carrier concentration and electron mobility, which is independent of the La dopant ratio, and provides an effective strategy for optimizing the electrical properties of BLSO films. [ABSTRACT FROM AUTHOR]

Epitaxial thin films of tantalum‐doped β‐Ga2O3 (Ta‐Ga2O3) are grown on MgO (001) substrates to study the effect of Ta doping on the electrical properties of β‐Ga2O3 films. X‐Ray diffraction (XRD) measurements show that the films with different Ta doping concentrations are (00l)‐oriented single‐crystalline β‐Ga2O3 without impurity phases. The incorporation of the Ta element modifies the electrical properties of Ta‐Ga2O3 films significantly. At a very low doping ratio of 0.05 mol%, the Ta‐Ga2O3 film showed a minimum resistivity of 2.32 Ω cm and a carrier concentration of 2.48 × 1017 cm−3. The corresponding activation energy of Ta element in the film is 16.8 meV, suggesting that the Ta element is a promising shallow donor dopant. The X‐ray photoelectron spectroscopy (XPS) analysis confirms that the Fermi level of the Ga2O3 films shifts toward the conduction band minimum after the introduction of Ta ions. These results indicate that the transition metal element Ta could be an effective n‐type dopant for modulating the carrier transport behavior of β‐Ga2O3 films. [ABSTRACT FROM AUTHOR]

In order to determine the physiological mechanism of drought resistance of northern wheat in China, six drought resistant wheat and one sensitivity to drought wheat were planted in pots. They were subjected to drought treatment and normal water when the plants grew to the 3-leaf stage. Samples were collected at 10, 20, 30, and 40 days after the drought treatment, respectively. The electrical conductivity, photosynthetic parameters, chlorophyll fluorescence parameters, sugar content, proline content, protein content, and active oxygen scavenging enzyme activity of the plants were detected, and the agronomic traits of the wheat varieties were investigated at maturity. The results indicated that the phenotype and yield-related factors of Darkhan 144 changed little under the drought stress. The relative electrical conductivity of Kefeng 6 and Darkhan 166 was lower under the drought stress, and their cell membrane was less damaged. The Darkhan 144 and Darkhan 166 had higher drought resistance coefficients, and were the wheat varieties with stronger drought resistance. However, the physiological mechanisms of drought resistance of these three wheat were different: Darkhan 144 maintained a higher photosynthetic activity under the drought stress; Darkhan 166 maintained a higher protein content, photosynthetic activity and active oxygen scavenging enzyme activity. In addition, other drought-resistant varieties Kefeng 6, Kefeng 10 and Longmai 26 had a higher content of osmoregulatory substances under the drought stress. [ABSTRACT FROM AUTHOR]

Herein, the use of a Hf doping strategy in epitaxial β‐Ga2O3 thin films is demonstrated to substantially enhance the conductivity and simultaneously achieve an even wider bandgap. Epitaxial β‐Ga2O3 thin films with various Hf dopant ratios are fabricated by pulsed laser deposition. The doping impact on the structural, optical, and transport properties is systematically investigated. At an optimized doping regime of 1%–2% in molar ratio, the heteroepitaxial Hf‐doped β‐Ga2O3 (Hf‐Ga2O3) films grown on the MgO substrate achieve a high n‐type conductivity of 6.5 S cm−1, a carrier mobility of 1.8 cm2 V−1 s−1, a carrier concentration of 2.69 × 1019 cm−3, and an ultrawide bandgap of 4.9 eV. The electron transport is further enhanced for the homoepitaxial Hf‐Ga2O3 film that exhibits a conductivity of 1236 S cm−1 and an ultrahigh mobility of 113 cm2 V−1 s−1. Density functional theory calculations reveal the preferential atomic site of Hf dopants in the β‐Ga2O3 lattice and its impact on the optical bandgap. This study demonstrates an effective way to achieve degenerate n‐type doping in ultrawide‐bandgap semiconductors for developing optoelectronic and power electronic devices. [ABSTRACT FROM AUTHOR]

Key message: Two wheat–Ae. longissima translocation chromosomes (1BS·1SlL and 1SlS·1BL) were transferred into three commercial wheat varieties, and the new advanced lines showed improved bread-making quality compared to their recurrent parents. Aegilops longissima chromosome 1Sl encodes specific types of gluten subunits that may positively affect wheat bread-making quality. The most effective method of introducing 1Sl chromosomal fragments containing the target genes into wheat is chromosome translocation. Here, a wheat–Ae. longissima 1BS·1SlL translocation line was developed using molecular marker-assisted chromosome engineering. Two types of translocation chromosomes developed in a previous study, 1BS·1SlL and 1SlS·1BL, were introduced into three commercial wheat varieties (Ningchun4, Ningchun50, and Westonia) via backcrossing with marker-assisted selection. Advanced translocation lines were confirmed through chromosome in situ hybridization and genotyping by target sequencing using the wheat 40 K system. Bread-making quality was found to be improved in the two types of advanced translocation lines compared to the corresponding recurrent parents. Furthermore, 1SlS·1BL translocation lines displayed better bread-making quality than 1BS·1SlL translocation lines in each genetic background. Further analysis revealed that high molecular weight glutenin subunit (HMW-GS) contents and expression levels of genes encoding low molecular weight glutenin subunits (LMW-GSs) were increased in 1SlS·1BL translocation lines. Gliadin and gluten-related transcription factors were also upregulated in the grains of the two types of advanced translocation lines compared to the recurrent parents. This study clarifies the impacts of specific glutenin subunits on bread-making quality and provides novel germplasm resources for further improvement of wheat quality through molecular breeding. [ABSTRACT FROM AUTHOR]

With the urgent demand for low power consumption, environment-friendly, and portable devices, self-powered solar-blind ultraviolet (UV) photodetectors that only rely on built-in electric fields without external power sources have received extensive attention. In this paper, we have demonstrated a self-powered solar-blind UV photodetector based on a 4H-SiC/ZnGa2O4 heterojunction, along with its application in optical communication. At 0 V bias, the device exhibits a peak responsivity of 115 mA/W with an external quantum efficiency of 58.4% at 244 nm, a fast response speed with a rise/decay time of 18.36/16.15 ms, and a high UV-vis rejection ratio of 4.5 × 104, suggesting that the device has an excellent self-powered solar-blind UV photodetection performance. The exceptional performance of the photodetector is mainly attributed to the 4H-SiC/ZnGa2O4 type I heterojunction with a large conduction band offset (ΔEC = 0.99 eV) and a large valence band offset (ΔEV = 0.75 eV), which is determined by the x-ray photoelectron spectroscopy technique. Moreover, the solar-blind UV optical communication is realized by utilizing the 4H-SiC/ZnGa2O4 heterojunction device to receive signals modulated by the solar-blind UV light. This work provides an effective approach to realizing high-performance self-powered solar-blind UV photodetectors and their potential applications in optical communication. [ABSTRACT FROM AUTHOR]

Here we investigate the influence of in situ ozone treatment on structure and carrier transport in La-doped BaSnO3 BLSO) films. It is found that introducing ozone during the film growth significantly inhibits the formation of oxygen vacancies and the occurrence of Sn2+ ions. The amount of oxygen vacancies decreases consistently with the increase of the ozone content, which further increases the in-plane lattice constant along with the relief of the in-plane compressive strain. More importantly, the reduction of oxygen vacancies gives rise to the augment of the threading dislocation density in the BLSO films, leading to the deterioration of carrier mobility. These findings demonstrate that the existence of Sn2+ ions does not apparently suppress the electron mobility in BLSO films, and the presence of oxygen vacancies is beneficial for reducing the density of threading dislocations, facilitating the mobility enhancement. All these findings would be beneficial for understanding the role of oxygen vacancy in carrier transport properties and for further optimizing the mobility of BLSO films. [ABSTRACT FROM AUTHOR]