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Mix‐dimensional heterojunctions (MDHJs) photodetectors (PDs) built from bulk and 2D materials are the research focus to develop hetero‐integrated and multifunctional optoelectronic sensor systems. However, it is still an open issue for achieving multiple effects synergistic characteristics to boost sensitivity and enrich the prospect in artificial bionic systems. Herein, electrically tunable Te/WSe2 MDHJs phototransistors are constructed, and an ultralow dark current below 0.1 pA and a large on/off rectification ratio of 106 is achieved. Photoconductive, photovoltaic, and photo‐thermoelectric conversions are simultaneously demonstrated by tuning the gate and bias. By these synergistic effects, responsivity and detectivity respectively reach 13.9 A W−1 and 1.37 × 1012 Jones with 400 times increment. The Te/WSe2 MDHJs PDs can function as artificial bionic visual systems due to the comparable response time to those of the human visual system and the presence of transient positive and negative response signals. This work offers an available strategy for intelligent optoelectronic devices with hetero‐integration and multifunctions. [ABSTRACT FROM AUTHOR]

In this study, yttrium iron garnet co‐doped with Zn and Zr atoms with a chemical formula Y3ZnxZrxFe(5−2x)O12 (x = 0.0‐0.3) has been successfully prepared by the solid‐state reaction method. The effects of doping concentration on the microstructure, crystal structure, magnetic properties, and dielectric properties of Y3ZnxZrxFe(5−2x)O12 were investigated. The microstructure analysis indicates that co‐doping of YIG with Zn and Zr can effectively reduce the grain size of the ceramic. The crystal structure results reveal that the doping concentration of Zn–Zr has substantial influence on the lattice parameters of YIG, such as, increases the lattice constant, crystal cell size, and interplanar spacing. However, the second phase of ZrO2 appears once x ≥ 0.15. Additionally, the dielectric properties of YIG ferrite can be regulated using this Zn–Zr co‐doping method. Zn–Zr co‐doping can improve the dielectric stability and reduce the dielectric loss at high temperature. The magnetization measurement shows that the saturation magnetization is stabilized at x < 0.15, and the magnetic loss is decreased with the increase in the doping concentration. Overall, the findings show that the ceramic with x = 0.1 exhibits better properties included high saturation magnetization (24.607 emu/g), low magnetic loss (0.0025 @ 1 MHz), and relatively low dielectric loss (496 @ 400°C). [ABSTRACT FROM AUTHOR]

[Display omitted] • ZB-MnTe thin films are epitaxially grown by MBE in spite of the metastable nature. • High-crystalline quality, atomic surface flatness and sharp interface are yielded. • PL emissions of 4 T 1g (4 G) and 4 T 1 (4 G) related to Mn2+ d - d multiplets are observed. • Two extra PL transitions attributed to STE states are demonstrated below T N. • Dynamics of photoexcited d -electrons are strongly correlated to the AFM transition. Single-crystalline γ -MnTe thin films with zinc-blende structure were grown epitaxially on InP(1 1 1) by molecular beam epitaxy. Two-dimensional growth regime and atomic surface flatness are achieved, and appearance of Laue's oscillation peaks illustrates the superior crystalline quality and interface of γ -MnTe films. A pseudocrystal buffer layer is formed at interface releasing the strain led by the large lattice mismatch between γ -MnTe and InP, and then growth of γ -MnTe films with a perfect lattice evidences the high-quality crystallinity in a fully relaxed state. Photoluminescence (PL) emissions from 4 T 1g (4 G) and 4 T 1 (4 G) related to Mn2+ ions d - d multiplets are observed with their respective activation energies of ∼142.5 meV and ∼323.5 meV. Such high potentials reflecting the nonradiative recombination indicate the thermal stability of these PL. Moreover, two extra PL transitions assigned to be the emissions from self-trapped exciton (STE) states are found below T N. Time-resolved PL (TRPL) spectra at various temperatures indicate that the relaxation dynamics of photoexcited d -electrons is strongly correlated to the antiferromagnetic ordering transition due to the synergy of magnon, phonon and STE states. These findings suggest that introduction of STE states in a material by controlling its magnetic ordering qualifies the competition in optoelectronics devices. [ABSTRACT FROM AUTHOR]

Two-dimensional GaGeTe flakes with different thicknesses from 80 to 2.2 nm (bilayer) were exfoliated and transferred to a SiO2/Si substrate. A series of samples with different thicknesses were prepared and identified by optical microscopy, atomic force microscopy, and Raman spectrum. Raman modes strongly dependent on the layer thickness and characteristic Raman-active modes for few-layer (FL) GaGeTe flakes are demonstrated. These vibration modes of FL GaGeTe show a linear red-shift phenomenon with increasing temperature and their full width at half maximum of the Raman mode exhibits a weak temperature dependence below 200 K, and then, a linear increase with temperature. The electrical conductivity is 96.48 S/cm for 74 nm flakes and drops exponentially to 2.27 × 10−7 S/cm for 7 nm ones because of the bandgap widening with the decrease of layer thickness, which is evidenced by the work function increase from 4.4 to 4.96 eV, when the thickness decreases from 80 to 2.2 nm. Moreover, the electrical conductivity performs two different temperature dependence behaviors on the thickness, indicating a transition from semimetal for bulk to semiconductor for FL GaGeTe, which agrees well with that of the theoretical calculation. [ABSTRACT FROM AUTHOR]

Laterally epitaxial two‐dimensional (2D) transition metal dichalcogenides (TMDs) heterojunctions are of considerable interest in recent years due to atomically sharp interfaces and tunable band alignment, which have potential applications in novel functional electronics and optoelectronics. However, the studies of 2D lateral heterostructures have mainly focused on the synthesis methods and pristine performance of the fabricated heterojunctions. Herein, the controllable photocurrent generation and enhanced performances of the lateral bilayer (LBL) MoS2–WS2 heterojunctions are reported. A tunable and abrupt built‐in field forms at the interface, and the gate‐tunable rectifying behavior and photovoltaic effect are realized. It is demonstrated that the generation of the photocurrent in the device can be highly controlled to realize ultrahigh responsivity of 1.06 × 104 A W−1 and detectivity of 1.14 × 1013 Jones at a 638 nm incident light. The lateral TMDs heterostructures are expected to constitute the ultimate functional elements of novel electronics and optoelectronics. [ABSTRACT FROM AUTHOR]