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<jats:p>Torque measurements were performed on single crystal samples of Ca<jats:sub>0.73</jats:sub>La<jats:sub>0.27</jats:sub>(Fe<jats:sub>0.96</jats:sub>Co<jats:sub>0.04</jats:sub>)As<jats:sub>2</jats:sub> in both the normal and superconducting states. Contributions to the torque signal from the paramagnetism and the vortex lattice were identified. The superconducting anisotropy parameter <jats:italic>γ</jats:italic> was determined from the reversible part of the vortex contribution based on Kogan’s model. It is found that <jats:italic>γ</jats:italic> ≃ 7.5 at <jats:italic>t</jats:italic> = <jats:italic>T</jats:italic>/<jats:italic>T</jats:italic> <jats:sub>c</jats:sub> = 0.85, which is smaller than the result of CaFe<jats:sub>0.88</jats:sub>Co<jats:sub>0.12</jats:sub>AsF <jats:italic>γ</jats:italic> ≃ 15 at <jats:italic>t</jats:italic> = 0.83, but larger than the result of 11 and 122 families, where <jats:italic>γ</jats:italic> stays in the range of 2–3. The moderate anisotropy of this 112 iron-based superconductor fills the gap between 11, 122 families and 1111 families. In addition, we found that the <jats:italic>γ</jats:italic> shows a temperature dependent behavior, i.e., decreasing with increasing temperature. The fact that <jats:italic>γ</jats:italic> is not a constant point towards a multiband scenario in this compound.</jats:p>

<jats:p>Despite the apparent ubiquity and variety of quantum spin liquids in theory, experimental confirmation of spin liquids remains to be a huge challenge. Motivated by the recent surge of evidences for spin liquids in a series of candidate materials, we highlight the experimental schemes, involving the thermal Hall transport and spectrum measurements, that can result in smoking-gun signatures of spin liquids beyond the usual ones. For clarity, we investigate the square lattice spin liquids and theoretically predict the possible phenomena that may emerge in the corresponding spin liquids candidates. The mechanisms for these signatures can be traced back to either the intrinsic characters of spin liquids or the external field-driven behaviors. Our conclusion does not depend on the geometry of lattices and can broadly apply to other relevant spin liquids.</jats:p>

<jats:p>The multiple ferroelectric polarization tuned by external electric field could be used to simulate the biological synaptic weight. Ferroelectric synaptic devices have two advantages compared with other reported ones: One is that the intrinsic switching of ferroelectric domains without invoking of defect migration as in resistive oxides, contributes reliable performance in these ferroelectric synapses. Another tremendous advantage is the extremely low energy consumption because the ferroelectric polarization is manipulated by electric field which eliminates the Joule heating by current as in magnetic and phase change memories. Ferroelectric synapses have potential for the construction of low-energy and effective brain-like intelligent networks. Here we summarize recent pioneering work of ferroelectric synapses involving the structure of ferroelectric tunnel junctions (FTJs), ferroelectric diodes (FDs), and ferroelectric field effect transistors (FeFETs), respectively, and shed light on future work needed to accelerate their application for efficient neural network.</jats:p>

<jats:p>By dispersing La<jats:sub>1 – <jats:italic>x</jats:italic> </jats:sub>Sr<jats:sub> <jats:italic>x</jats:italic> </jats:sub>MnO<jats:sub>3</jats:sub> (LSMO) granule into PbZr<jats:sub> <jats:italic>x</jats:italic> </jats:sub>Ti<jats:sub>1 – <jats:italic>x</jats:italic> </jats:sub>O<jats:sub>3</jats:sub> (PZT) matrix, the 0-3 type LSMO/PZT composite film is synthesized through chemical solution method. The asymmetry of the top and bottom electrodes introduces novel electrostatic screening on LSMO/PZT interface. As electric polarization is switched between upward and downward orientations, the evolution of exchange bias, diode transport, and magnetoresistance is observed. The result implies the electrostatic switch of magnetic core-shell in the present film. In detail, as the spontaneous polarization is upward or downward in the PZT matrix, the ferromagnetic/antiferromagnetic or ferromagnetic/ferromagnetic core-shell structure is formed in LSMO granule, respectively. This work would develop a novel device for spintronics and metamaterial.</jats:p>

<jats:p>Recently, neuromorphic devices for artificial intelligence applications have attracted much attention. In this work, a three-terminal electrolyte-gated synaptic transistor based on NdNiO<jats:sub>3</jats:sub> epitaxial films, a typical correlated electron material, is presented. The voltage-controlled metal–insulator transition was achieved by inserting and extracting H<jats:sup>+</jats:sup> ions in the NdNiO<jats:sub>3</jats:sub> channel through electrolyte gating. The non-volatile conductance change reached 10<jats:sup>4</jats:sup> under a 2 V gate voltage. By manipulating the amount of inserted protons, the three-terminal NdNiO<jats:sub>3</jats:sub> artificial synapse imitated important synaptic functions, such as synaptic plasticity and spike-timing-dependent plasticity. These results show that the correlated material NdNiO<jats:sub>3</jats:sub> has great potential for applications in neuromorphic devices.</jats:p>

<jats:p>Diamond crystallization was carried out with CH<jats:sub>4</jats:sub>N<jats:sub>2</jats:sub>S additive in the FeNiCo-C system at pressure 6.0 GPa and temperature ranging from 1290 °C to 1300 °C. The crystallization qualities of the synthetic crystals were characterized by Raman spectra and the Raman peaks located at 1331 cm<jats:sup>−1</jats:sup>. Fourier transform infrared (FTIR) results showed that the hydrogen-related absorption peak of the as-grown diamond was at 2920 cm<jats:sup>−1</jats:sup>, respectively. Interestingly, A-center nitrogen was observed in the obtained diamond and the characteristic absorption peaks located at 1095 cm<jats:sup>−1</jats:sup> and 1282 cm<jats:sup>−1</jats:sup>. Especially, the absorption peak at 1426 cm<jats:sup>−1</jats:sup> attributing to the aggregation B-center nitrogen defect was distinctly found when the CH<jats:sub>4</jats:sub>N<jats:sub>2</jats:sub>S content reached 0.3 mg in the synthesis system, which was extremely rare in synthetic diamond. Furthermore, optical color centers in the synthesized crystals were investigated by photoluminescence (PL).</jats:p>

<jats:p>Significant electric control of exchange bias effect in a simple CoO<jats:sub>1–<jats:italic>δ</jats:italic> </jats:sub>/Co system, grown on piezoelectric Pb(Mg<jats:sub>1/3</jats:sub>Nb<jats:sub>2/3</jats:sub>)<jats:sub>0.7</jats:sub>Ti<jats:sub>0.3</jats:sub>O<jats:sub>3</jats:sub> (110) (PMN-PT) substrates, is achieved at room temperature. Obvious changes in both the coercivity field (<jats:italic>H</jats:italic> <jats:sub>C</jats:sub>) and the exchange bias field (<jats:italic>H</jats:italic> <jats:sub>E</jats:sub>), of 31% and 5%, respectively, have been observed when the electric field is applied to the substrate. While the change of coercivity is related to the enhanced uniaxial anisotropy in the ferromagnetic layer, the change of the exchange bias field can only originate from the spin reorientation in the antiferromagnetic CoO<jats:sub>1–<jats:italic>δ</jats:italic> </jats:sub> layer caused by the strain-induced magnetoelastic effect. A large <jats:italic>H</jats:italic> <jats:sub>E</jats:sub>/<jats:italic>H</jats:italic> <jats:sub>C</jats:sub> &gt; 2, and <jats:italic>H</jats:italic> <jats:sub>E</jats:sub> ∼ 110 Oe at room temperature, as well as the low-energy fabrication of this system, make it a practical system for spintronic device applications.</jats:p>

<jats:p>Self-powered photodetectors based on nanomaterials have attracted lots of attention for several years due to their various advantages. In this paper, we report a high performance Cu<jats:sub>2</jats:sub>O/ZnO self-powered photodetector fabricated by using electrochemical deposition. ZnO nanowires arrays grown on indium-tin-oxide glass are immersed in Cu<jats:sub>2</jats:sub>O film to construct type-II band structure. The Cu<jats:sub>2</jats:sub>O/ZnO photodetector exhibits a responsivity of 0.288 mA/W at 596 nm without bias. Compared with Cu<jats:sub>2</jats:sub>O photoconductive detector, the responsivity of the Cu<jats:sub>2</jats:sub>O/ZnO self-powered photodetector is enhanced by about two times at 2 V bias. It is attributed to the high power conversion efficiency and the efficient separation of the photogenerated electron–hole pairs, which are provided by the heterojunction. The outstanding comprehensive performances make the Cu<jats:sub>2</jats:sub>O film/ZnO nanowires self-powered photodetector have great potential applications.</jats:p>

<jats:p>The process of <jats:italic>in situ</jats:italic> tumors developing into malignant tumors and exhibiting invasive behavior is extremely complicated . From a biophysical point of view, it is a phase change process affected by many factors, including cell-to-cell, cell-to-chemical material, cell-to-environment interaction, <jats:italic>etc</jats:italic>. In this study, we constructed spheroids based on green fluorescence metastatic breast cancer cells MDA-MB-231 to simulate malignant tumors <jats:italic>in vitro</jats:italic>, while constructed a three-dimensional (3D) biochip to simulate a micro-environment for the growth and invasion of spheroids. In the experiment, the 3D spheroid was implanted into the chip, and the oriented collagen fibers controlled by collagen concentration and injection rate could guide the MDA-MB-231 cells in the spheroid to undergo directional invasion. The experiment showed that the oriented fibers greatly accelerated the invasion speed of MDA-MB-231 cells compared with the traditional uniform tumor micro-environment, namely obvious invasive branches appeared on the spheroids within 24 hours. In order to analyze this interesting phenomenon, we have developed a quantitative analyzing approach to explore strong angle correlation between the orientation of collagen fibers and invasive direction of cancer cell. The results showed that the oriented collagen fibers produced by the chip can greatly stimulate the invasion potential of cancer cells. This biochip is not only conducive to modeling cancer cell metastasis and studying cell invasion mechanisms, but also has the potential to build a quantitative evaluation platform that can be used in future chemical drug treatments.</jats:p>

<jats:p>The cadmium sulphide (CdS) film is grown on cadmium telluride (CdTe) nanorods (NRs) arrays by different methods such as chemical bath deposition (CBD), magnetron sputtering (MS), and homogenous precipitation (HP) techniques. The impact of various deposition methods is explored in detail on the growth of CdTe/CdS composite film, the CdTe/CdS interface property, and solar cell efficiency. Compared to the CBD and HP methods, the MS method can improve the growth of the CdS on CdTe NRs with high crystalline quality. The device based on the CdS film prepared by the MS method demonstrates excellent photovoltaic performance, which has the potential for applications in solar cells.</jats:p>