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<jats:p>A gradient refractive structured NiCr film that has a high extinction coefficient at far infrared range (8-<jats:inline-formula> <jats:tex-math><?CDATA ${\rm{\mu }}{\rm{m}}$?></jats:tex-math> <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:mi mathvariant="normal">μ</mml:mi> <mml:mi mathvariant="normal">m</mml:mi> </mml:math> <jats:inline-graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="cpb_28_6_067801_ieqn1.gif" xlink:type="simple" /> </jats:inline-formula>–<jats:inline-formula> <jats:tex-math><?CDATA $24\,{\rm{\mu }}{\rm{m}}$?></jats:tex-math> <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:mn>24</mml:mn> <mml:mspace width="0.50em" /> <mml:mi mathvariant="normal">μ</mml:mi> <mml:mi mathvariant="normal">m</mml:mi> </mml:math> <jats:inline-graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="cpb_28_6_067801_ieqn2.gif" xlink:type="simple" /> </jats:inline-formula>) is presented as an absorber for pyroelectric infrared detectors. The absorber features high absorption efficiency due to the low reflection off the structured surface and high absorption across the film thickness. The refractive index and extinction coefficient are extracted using spectroscopic ellipsometry. It is found that the single NiCr film exhibits an increasing refractive index as the gas atmosphere pressure increases, hence the three-layer gradient NiCr absorber can be fabricated by adjusting the gas atmosphere pressure during sputtering deposition. Essential Macleod software has been used to generate an efficient film structure design and the calculations show similar absorptance trend compared to the experimental measurement result. The results indicate that the gradient refractive structured metal thin film absorber can provide high absorption for applications in thermal sensing.</jats:p>

<jats:p> <jats:italic>In situ</jats:italic> Raman spectroscopy and x-ray diffraction measurements are used to explore the structural stability of CaB<jats:sub>6</jats:sub> at high pressures and room temperature. The results show no evidence of structural phase transitions up to at least 40 GPa. The obtained equation of state with smooth pressure dependencies yields a zero-pressure isothermal bulk modulus <jats:italic>B</jats:italic> <jats:sub>0</jats:sub> = 170 (5) GPa, which agrees well with the previous measurements. The frequency shifts for A<jats:sub>1g</jats:sub>, E<jats:sub>g</jats:sub>, and T<jats:sub>2g</jats:sub> vibrational modes of polycrystalline CaB<jats:sub>6</jats:sub> are obtained with pressure uploading. As the pressure increases, all the vibration modes have smooth monotonic pressure dependence. The Grüneisen parameter of E<jats:sub>g</jats:sub> modes is the largest, indicating its largest dependence on the volume of a crystal lattice.</jats:p>

<jats:p>Uniform mixing of ceramic powder and graphene is of great importance for producing ceramic matrix composite. In this study, graphene nanowalls (GNWs) are directly deposited on the surface of Al<jats:sub>2</jats:sub>O<jats:sub>3</jats:sub> and Si<jats:sub>3</jats:sub>N<jats:sub>4</jats:sub> powders using chemical vapor deposition system to realize the uniform mixing. The morphology and the initial stage of the growth process are investigated. It is found that the graphitic base layer is initially formed parallel to the powder surface and is followed by the growth of graphene nanowalls perpendicular to the surface. Moreover, the lateral length of the graphene sheet could be well controlled by tuning the growth temperature. GNWs/Al<jats:sub>2</jats:sub>O<jats:sub>3</jats:sub> powder is consolidated by using sparking plasma sintering method and several physical properties are measured. Owing to the addition of GNWs, the electrical conductivity of the bulk alumina is significantly increased.</jats:p>

<jats:p>We present a self-assembly method to prepare array nano-wires of colloidal CdSe quantum dots on a substrate of porous Al<jats:sub>2</jats:sub>O<jats:sub>3</jats:sub> film modified by gold nanoparticles. The photoluminescence (PL) spectra of nanowires are in situ measured by using a scanning near-field optical microscopy (SNOM) probe tip with 100-nm aperture on the scanning near-field optical microscope. The results show that the binding sites from the edge of porous Al<jats:sub>2</jats:sub>O<jats:sub>3</jats:sub> nanopores are combined with the carboxyl of CdSe quantum dots’ surface to form an array of CdSe nanowires in the process of losing background solvent because of the gold nanoparticles filling the nano-holes of porous Al<jats:sub>2</jats:sub>O<jats:sub>3</jats:sub> film. Compared with the area of non-self-assembled nano-wire, the fluorescence on the Al<jats:sub>2</jats:sub>O<jats:sub>3</jats:sub>/Au/CdSe interface is significantly enhanced in the self-assembly nano-wire regions due to the electron transfer conductor effect of the gold nanoparticles’ surface. In addition, its full width at half maximum (FWHM) is also obviously widened. The method of enhancing fluorescence and energy transfer can widely be applied to photodetector, photocatalysis, optical display, optical sensing, and biomedical imaging, and so on.</jats:p>

<jats:p>A single-phase iron oxide Ba<jats:sub>0.8</jats:sub>Sr<jats:sub>0.2</jats:sub>FeO<jats:sub>3-<jats:italic>δ</jats:italic> </jats:sub> with a simple cubic perovskite structure in <jats:italic>Pm</jats:italic>-3<jats:italic>m</jats:italic> symmetry is successfully synthesized by a solid-state reaction method in O<jats:sub>2</jats:sub> flow. The oxygen content is determined to be about 2.81, indicating the formation of mixed Fe<jats:sup>3+</jats:sup> and Fe<jats:sup>4+</jats:sup> charge states with a disorder fashion. As a result, the compound shows small-polaron conductivity behavior, as well as spin glassy features arising from the competition between the ferromagnetic interaction and the antiferromagnetic interaction. Moreover, the competing interactions also give rise to a remarkable exchange bias effect in Ba<jats:sub>0.8</jats:sub>Sr<jats:sub>0.2</jats:sub>FeO<jats:sup>2.81</jats:sup>, providing an opportunity to use it in spin devices.</jats:p>

<jats:p>Silicon monoxide (SiO) has been considered as one of the most promising anode materials for next generation high-energy-density Li-ion batteries (LiBs) thanks to its high theoretical capacity. However, the poor intrinsic electronic conductivity and large volume change during lithium intercalation/de-intercalation restrict its practical applications. Fabrication of SiO/C composites is an effective way to overcome these problems. Herein, a series of micro-sized SiO@C/graphite (SiO@C/G) composite anode materials, with designed capacity of <jats:inline-formula> <jats:tex-math><?CDATA $600\,\mathrm{mAh}\cdot {{\rm{g}}}^{-1}$?></jats:tex-math> <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:mn>600</mml:mn> <mml:mspace width="0.25em" /> <mml:mi>mAh</mml:mi> <mml:mo>·</mml:mo> <mml:msup> <mml:mrow> <mml:mi mathvariant="normal">g</mml:mi> </mml:mrow> <mml:mrow> <mml:mo>−</mml:mo> <mml:mn>1</mml:mn> </mml:mrow> </mml:msup> </mml:math> <jats:inline-graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="cpb_28_6_068201_ieqn1.gif" xlink:type="simple" /> </jats:inline-formula>, are successfully prepared through a pitch pyrolysis reaction method. The electrochemical performance of SiO@C/G composite anodes with different carbon coating contents of 5 wt%, 10 wt%, 15 wt%, and 35 wt% is investigated. The results show that the SiO@C/G composite with 15-wt% carbon coating content exhibits the best cycle performance, with a high capacity retention of 90.7% at 25 °C and 90.1% at 45 °C after 100 cycles in full cells with LiNi<jats:sub>0.5</jats:sub>Co<jats:sub>0.2</jats:sub>Mn<jats:sub>0.3</jats:sub>O<jats:sub>2</jats:sub> as cathodes. The scanning electron microscope (SEM) and electrochemistry impedance spectroscopy (EIS) results suggest that a moderate carbon coating layer can promote the formation of stable SEI film, which is favorable for maintaining good interfacial conductivity and thus enhancing the cycling stability of SiO electrode.</jats:p>

<jats:p>Li(Ni<jats:sub>0.6</jats:sub>Co<jats:sub>0.2</jats:sub>Mn<jats:sub>0.2</jats:sub>)O<jats:sub>2</jats:sub> has been surface-modified by the lithium-ion conductor Li<jats:sub>1.4</jats:sub>)Al<jats:sub>0.4</jats:sub>)Ti<jats:sub>1.6</jats:sub>)(PO<jats:sub>4</jats:sub>)<jats:sub>3</jats:sub> via a facile mechanical fusion method. The annealing temperature during coating process shows a strong impact on the surface morphology and chemical composition of Li(Ni<jats:sub>0.6</jats:sub>Co<jats:sub>0.2</jats:sub>Mn<jats:sub>0.2</jats:sub>)O<jats:sub>2</jats:sub>. The 600-°C annealed material exhibits the best cyclic stability at high charging cut-off voltage of 4.5 V (<jats:italic>versus</jats:italic> Li <jats:inline-formula> <jats:tex-math> <?CDATA ${}^{+}$?> </jats:tex-math> <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:msup> <mml:mrow /> <mml:mrow> <mml:mo>+</mml:mo> </mml:mrow> </mml:msup> </mml:math> <jats:inline-graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="cpb_28_6_068202_ieqn1.gif" xlink:type="simple" /> </jats:inline-formula>/Li) with the capacity retention of 90.9% after 100 cycles, which is much higher than that of bare material (79%). Moreover, the rate capability and thermal stability are also improved by Li<jats:sub>1.4</jats:sub>)Al<jats:sub>0.4</jats:sub>)Ti<jats:sub>1.6</jats:sub>)(PO<jats:sub>4</jats:sub>)<jats:sub>3</jats:sub> coating. The enhanced performance can be attributed to the improved stability of interface between Li(Ni<jats:sub>0.6</jats:sub>Co<jats:sub>0.2</jats:sub>Mn<jats:sub>0.2</jats:sub>)O<jats:sub>2</jats:sub> and electrolyte by Li<jats:sub>1.4</jats:sub>)Al<jats:sub>0.4</jats:sub>)Ti<jats:sub>1.6</jats:sub>)(PO<jats:sub>4</jats:sub>)<jats:sub>3</jats:sub> modification. The results of this work provide a possible method to design reliable cathode materials to achieve high energy density and long cycle life.</jats:p>

<jats:p>Hard carbons as promising anode materials for Na-ion batteries (NIBs) have captured extensive attention because of their low operation voltage, easy synthesis process, and competitive specific capacity. However, there are still several disadvantages, such as high cost and low initial coulombic efficiency, which limit their large-scale commercial applications. Herein, pine nut shells (PNSs), a low-cost biomass waste, are used as precursors to prepare hard carbon materials. Via a series of washing and heat treatment procedures, a pine nut shell hard carbon (PNSHC)-1400 sample has been obtained and delivers a reversible capacity of around 300 mAh/g, a high initial coulombic efficiency of 84%, and good cycling performance. These excellent Na storage properties indicate that PNSHC is one of the most promising candidates of hard carbon anodes for NIBs.</jats:p>

<jats:p>The design, fabrication, and the characterization of a 0.5-V Josephson junction array device are presented for the quantum voltage standards in the National Institute of Metrology (NIM) of China. The device consists of four junction arrays, each of which has 1200 3-stacked Nb/Nb<jats:sub> <jats:italic>x</jats:italic> </jats:sub>Si<jats:sub>1−<jats:italic>x</jats:italic> </jats:sub>/Nb junctions and an on-chip superconducting microwave circuit which is mainly a power divider enabling each Josephson array being loaded with an equal amount of microwave power. A direct current (dc) quantum voltage of about 0.5 V with a ∼1-mA current margin of the 1st quantum voltage step is obtained. To further prove the quality of NIM device, a comparison between the NIM device with the National Institute of Standards and Technology (NIST) programmable Josephson voltage standard (PJVS) system device is conducted. The difference of the reproduced 0.5-V quantum voltage between the two devices is about 0.55 nV, which indicates good agreement between the two devices. With the homemade device, we have realized a precise and applicable 0.5-V applicable-level quantum voltage.</jats:p>

<jats:p>This paper proposes two optimal designs of single photon avalanche diodes (SPADs) minimizing dark count rate (DCR). The first structure is introduced as p<jats:sup>+</jats:sup>/pwell/nwell, in which a specific shallow pwell layer is added between p<jats:sup>+</jats:sup> and nwell layers to decrease the electric field below a certain threshold. The simulation results show on average 19.7% and 8.5% reduction of p<jats:sup>+</jats:sup>/nwell structure’s DCR comparing with similar previous structures in different operational excess bias and temperatures respectively. Moreover, a new structure is introduced as <jats:inline-formula> <jats:tex-math> <?CDATA ${{\rm{n}}}^{+}$?> </jats:tex-math> <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:msup> <mml:mrow> <mml:mi mathvariant="normal">n</mml:mi> </mml:mrow> <mml:mrow> <mml:mo>+</mml:mo> </mml:mrow> </mml:msup> </mml:math> <jats:inline-graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="cpb_28_6_068502_ieqn1.gif" xlink:type="simple" /> </jats:inline-formula>/nwell/pwell, in which a specific shallow nwell layer is added between n<jats:sup>+</jats:sup> and pwell layers to lower the electric field below a certain threshold. The simulation results show on average 29.2% and 5.5% decrement of <jats:inline-formula> <jats:tex-math> <?CDATA ${{\rm{p}}}^{+}$?> </jats:tex-math> <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:msup> <mml:mrow> <mml:mi mathvariant="normal">p</mml:mi> </mml:mrow> <mml:mrow> <mml:mo>+</mml:mo> </mml:mrow> </mml:msup> </mml:math> <jats:inline-graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="cpb_28_6_068502_ieqn2.gif" xlink:type="simple" /> </jats:inline-formula>/nwell structure’s DCR comparing with similar previous structures in different operational excess bias and temperatures respectively. It is shown that in higher excess biases (about 6 volts), the n<jats:sup>+</jats:sup>/nwell/pwell structure is proper to be integrated as digital silicon photomultiplier (dSiPM) due to low DCR. On the other hand, the p<jats:sup>+</jats:sup>/pwell/nwell structure is appropriate to be utilized in dSiPM in high temperatures (above 50 °C) due to lower DCR value.</jats:p>