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<jats:p> <jats:italic>Developing accurate self-assembly is the key for constructing functional materials from a bottom-up approach. At present, it is mainly hindered by building blocks and driving modes. We design a new self-assembly method based on the magnetic coupling between spin-polarized electrons. First-principles calculations show that spin-polarized electrons from different endohedral metallofullerene (EMF) superatoms can pair each other to ensure a one-dimensional extending morphology. Furthermore, without ligand passivation, the EMF superatoms maintain their electronic structures robustly in self-assembly owing to the core-shell structure and the atomic-like electron arrangement rule. Therefore, it should noted that the magnetic coupling of monomeric electron spin polarization can be an important driving mechanism for high-precision self-assembly. These results represent a new paradigm for self-assembly and offer fresh opportunities for functional material construction at the atomic level</jats:italic>.</jats:p>

<jats:p> <jats:italic>This work aims to study the N-coupled Hirota equations in an optical fiber under the zero boundary condition at infinity. By analyzing the spectral problem, a matrix Riemann–Hilbert problem on the real axis is strictly established. Then, by solving the presented matrix Riemann–Hilbert problem under the constraint of no reflection, the bright multi-soliton solutions to the N-coupled Hirota equations are explicitly gained</jats:italic>.</jats:p>

<jats:p> <jats:italic>Direct ZnO x-ray detectors with tunable sensitivity are realized by delicately controlling the oxygen flux during the sputtering deposition process. The photocurrents induced by x-rays from a 40 kV x-ray tube with a Cu anode increase apparently as the oxygen flux decreases, which is attributed to the introduction of V<jats:sub>o</jats:sub> detects. By introducing V<jats:sub>o</jats:sub> defects, the annihilation rate of the photo-generated electron-hole pairs will be greatly slowed down, leading to a remarkable photoconductive gain. This finding informs a novel way to design the x-ray detectors based on abundant oxide materials</jats:italic>.</jats:p>

<jats:p> <jats:italic>New experimental cross-section data for the <jats:sup>180</jats:sup>W(n,2n)<jats:sup>179m</jats:sup>W, <jats:sup>186</jats:sup>W(n,2n)<jats:sup>185m</jats:sup>W and <jats:sup>186</jats:sup>W(n,p)<jats:sup>186</jats:sup>Ta reactions at the neutron energies of 13.5 and 14.4 MeV are obtained by the activation technique. The neutron beams are produced by means of the <jats:sup>3</jats:sup>H(d,n)<jats:sup>4</jats:sup>He reaction. The gamma activities of the product nuclei are measured by a high-resolution gamma-ray spectrometer with a coaxial high-purity germanium detector. The neutron fluence is determined using the monitor reaction <jats:sup>93</jats:sup>Nb(n,2n)<jats:sup>92m</jats:sup>Nb. The results in the current work are discussed and compared with the measurement results found in the literature. It is shown that these higher accuracy experimental cross-section data around the neutron energy of 14 MeV agree with some previous experimental values from the literature within experimental uncertainties</jats:italic>.</jats:p>

<jats:p> <jats:italic>The field shift and mass shift parameters of the 2s2p <jats:sup>3,1</jats:sup>P<jats:sub>1</jats:sub> → 2s<jats:sup>2</jats:sup> <jats:sup>1</jats:sup>S<jats:sub>0</jats:sub> transitions in Be-like ions (70 ≤ Z ≤ 92) are calculated using the multi-configuration Dirac–Hartree–Fock and the relativistic configuration interaction methods with the inclusion of the Breit interaction and the leading QED corrections. We find that the mass shift parameters of these two transitions do not change monotonously along the isoelectronic sequence in the high-Z range due to the relativistic nuclear recoil effects. A minimum value exists for the specific mass shift parameters around Z = 80, especially for the 2s2p <jats:sup>3</jats:sup>P<jats:sub>1</jats:sub> → 2s<jats:sup>2</jats:sup> <jats:sup>1</jats:sup>S<jats:sub>0</jats:sub> transition. In addition, the field shifts and mass shifts of these two transitions are estimated using an empirical formula, and their contributions are compared along the isoelectronic sequence</jats:italic>.</jats:p>

<jats:p> <jats:italic>We demonstrate laser ultrasonic generation in polyetheretherketone (PEEK). A middle infrared ZnGeP<jats:sub>2</jats:sub> optical parametric oscillator (ZGP-OPO) pumped by a Q-switched Ho:YAG laser is employed as the ultrasonic excitation source. The ZGP-OPO has a spectral range of 3.2–3.4 μm. At an output wavelength of 3.4 μm, the maximum average output power of ZGP-OPO is 3.05 W with a pulse width of 24.3 ns, corresponding to a peak power of approximately 127.5 kW. The ultrasound is generated by the laser converted from 3.2 to 3.4 μm in the PEEK composite. The maximum ultrasonic signal amplitude in PEEK is 33 mV under the condition of thermoelastic excitation at 3.4 μm. Ablation occurs in the CPRF sample when the energy fluence is over 122.45 mJ/cm<jats:sup>2</jats:sup>. PEEK has a stronger absorption at 3.4 μm and laser-ultrasound generation is influenced by the wavelength of the laser</jats:italic>.</jats:p>

<jats:p> <jats:italic>We develop a two-stage end-pumped Nd:YVO<jats:sub>4</jats:sub> amplifier seeded by a passively Q-switched microchip laser. An average output power of 13.5 W with repetition rate up to 7 kHz and pulse duration of ∼1.24 ns is obtained, corresponding to a pump extraction efficiency of 16.1% (19.5% for the second stage) and peak power of ∼1.5 MW. The beam quality factors at maximum output power are measured to be</jats:italic> <jats:inline-formula> <jats:tex-math><?CDATA ${M}_{x}^{2}=1.56$?></jats:tex-math> <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:mrow> <mml:msubsup> <mml:mi>M</mml:mi> <mml:mi>x</mml:mi> <mml:mn>2</mml:mn> </mml:msubsup> <mml:mo>=</mml:mo> <mml:mn>1.56</mml:mn> </mml:mrow> </mml:math> <jats:inline-graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="cpl_36_11_114202_ieqn1.gif" xlink:type="simple" /> </jats:inline-formula> <jats:italic>and</jats:italic> <jats:inline-formula> <jats:tex-math><?CDATA ${M}_{y}^{2}=1.48$?></jats:tex-math> <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:mrow> <mml:msubsup> <mml:mi>M</mml:mi> <mml:mi>y</mml:mi> <mml:mn>2</mml:mn> </mml:msubsup> <mml:mo>=</mml:mo> <mml:mn>1.48</mml:mn> </mml:mrow> </mml:math> <jats:inline-graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="cpl_36_11_114202_ieqn2.gif" xlink:type="simple" /> </jats:inline-formula>. <jats:italic>We introduce an analytical model to estimate gain and beam quality after amplification. This model focuses on the influence of ratio of seed spot radius to pump spot radius when designing an amplifier. Moreover, our experiments reveal that the re-imaging system in the double-pass configuration can be used to enhance the beam quality</jats:italic>.</jats:p>

<jats:p> <jats:italic>Wavefront shaping technology has mainly been applied to microscopic fluorescence imaging through turbid media, with the advantages of high resolution and imaging depth beyond the ballistic regime. However, fluorescence needs to be introduced extrinsically and the field of view is limited by memory effects. Here we propose a new method for microscopic imaging light transmission through turbid media, which has the advantages of label-free and discretional field of view size, based on transmission-matrix-based wavefront shaping and the random matrix theory. We also verify that a target of absorber behind the strong scattering media can be imaged with high resolution in the experiment. Our method opens a new avenue for the research and application of wavefront shaping</jats:italic>.</jats:p>

<jats:p> <jats:italic>A target in layered medium can be located by the ridge-like distribution time reversal and reverse time migration (TR-RTM) mixed method. However, this method cannot distinguish between acoustic field distributions of the interface and target for the wider acoustic pulse signals, which may result in inaccurate location of the target. A snapshot TR-RTM mixed method is proposed to solve this problem. The principle of snapshot TR-RTM mixed method is first given. Experiments are then carried out, and a mountain-like acoustic field distribution is obtained by processing experimental data. The results show that the location of the peak is that of the target, and the ratio of the scattered signal and interface reflection signal (signal-to-interference ratio) is improved by about four times after processing. Furthermore, this method can effectively suppress the interface reflection signal and enhance the target scattering signal. Therefore, it can achieve effective detection and location of a target in a layered medium</jats:italic>.</jats:p>

<jats:p> <jats:italic>We propose an innovative method to generate acoustic vortex waves based on a disc piezoelectric transducer that is coated with multi-arm coiled electrodes. Finite element simulation results for single-arm to four-arm coiled electrodes indicate that the method could modulate amplitude and phase spatial distribution of the acoustic waves near the acoustic axis by acoustic field synthesis principle, making the waves rotate spirally in space and form stable focused vortex beams. Compared with the traditional method that requires electronic control of an array consisting of a large number of transducers, this method provides a more effective and compact solution.</jats:italic> </jats:p>