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<jats:title>Abstract</jats:title> <jats:p>An open quantum battery (QB) model of a single qubit system charging in a coherent auxiliary bath (CAB) consisting of a series of independent coherent ancillae is considered. Based on the collision charging protocol we drive the quantum master equation and obtain the analytical solution of QB at the steady state. We find that the full charging capacity (or the maximal extractable work (MEW)) of QB, in the weak QB-ancilla coupling limit, is positively correlated to the coherence magnitude of ancilla. Combing with the numerical simulations we compare with the charging properties of QB at finite coupling strength, such as the MEW, average charging power and the charging efficiency, when considering the bath being a thermal auxiliary bath (TAB) and a CAB, respectively. We find that when the QB with CAB, in the weak coupling regime, is in full charging both its capacity and charging efficiency can go beyond its classical counterpart, and they increase with the increase of coherence magnitude of ancilla. In addition, the MEW of QB, in the regime of relative strong coupling and strong coherent magnitude, shows the oscillatory behavior with the charging time, and the first peak value can even be larger than the full charging MEW of QB. This also leads to a much larger average charging power than that of QB with TAB in a short-time charging process. These features suggest that with the help of quantum coherence of CAB it becomes feasible to switch the charging schemes between the long-time slow charging protocol with large capacity and high efficiency and the short-time rapid charging protocol with highly charging power only by adjusting the coupling strength of QB-ancilla. This work clearly demonstrates that the quantum coherence of bath could not only serve as the role of “fuel” of QB to be utilized to improve the QB's charging performance but also provide an alternative way to integrate the different charging protocols into a single QB.</jats:p>

<jats:title>Abstract</jats:title> <jats:p>This work proposed to change the structure of the sample susceptor of the microwave plasma chemical vapor deposition (MPCVD) reaction chamber, that is, to introduce a small hole in the center of the susceptor to study its suppression effect on the incorporation of residual nitrogen in the MPCVD diamond film. Using COMSOL multiphysics software simulation, the plasma characteristics and the concentration of chemical reactants in the cylindrical cavity of MPCVD system were studied, including electric field intensity, electron number density, electron temperature, the concentrations of atomic hydrogen, methyl, and nitrogenous substances, etc. After introducing a small hole in the center of the molybdenum support susceptor, we found that no significant changes were found in the center area of the plasma, but the electron state in the plasma changed greatly on the surface above the susceptor. The electron number density was reduced by about 40%, while the electron temperature was reduced by about 0.02eV, and the concentration of atomic nitrogen has decreased by about an order of magnitude. Moreover, we found that if a specific lower microwave input power is used, and a susceptor structure without the small hole is introduced, the change results similar to those in the surface area of the susceptor will be obtained, but the spatial distribution of electromagnetic field and reactant concentration will be changed.</jats:p>

<jats:title>Abstract</jats:title> <jats:p>In this work, hydrogen-bonded polar nematic liquid crystal series with the general formula nOBAF (n = 7 - 12) were studied. The mesomorphic characterization was once demonstrated through differential scanning Calorimetry (DSC) and polarized optical microscopy (POM). The complexes with short alkyl chains (n=7, 8) presented a wide nematic range and monotropic smectic F mesophase, whereas the longer alkyl chain (n=10-12) analogues showed a high melting and low clearing mesomorphic liquid crystals. The thermal range of the mesophase and the birefringence were increased with reducing the chain length. Furthermore, the effect of the nanoparticles (LiNbO3) on the thermal and the electrical behavior of 8OBAF was investigated. The presence of LiNbO3 nanoparticles increased the conductivity and reduced the resistivity of the complex.</jats:p>

<jats:title>Abstract</jats:title> <jats:p>We explore the dynamical behaviors of the measuring uncertainty and quantum correlation in a vertical quantum dot system with the magnetic field, including electron-electron interaction and Coulomb-blocked systems. Stemming from the quantum-memory-assisted entropic uncertainty relation, the uncertainty of interest is associated with the temperature and the parameters related to the magnetic field. Interestingly, the temperature has two kinds of influences on the variation of measured uncertainty with respect to the parameters related to the magnetic field. We also discuss the relation between Berta <jats:italic>et al</jats:italic>.'s lower bound and the quantum discord and it has been found that there is a natural competition between the quantum discord and the entropy ${{\min _{\Pi _i^B}}{S_{\Pi _i^B}}\left( {{\rho _{A\left| B \right.}}} \right)}$. Finally, we bring in two improved bounds to offer a more precise limit to the entropic uncertainty.</jats:p>

<jats:title>Abstract</jats:title> <jats:p>In this work, we present a class of two-dimensional memristive maps with a cosine memristor. The memristive maps do not have any fixed points, so they belong to the category of nonlinear maps with hidden attractors. The rich dynamical behaviors of these maps are demonstrated and investigated using different numerical tools, including phase portrait, basins of attraction, bifurcation diagram, and Lyapunov exponents. The two-parameter bifurcation analysis of the memristive map has been carried out to reveal the bifurcation mechanism of the dynamical behaviors. Based on our extensive simulation studies, the proposed memristive maps can produce hidden periodic, chaotic, and hyper-chaotic attractors. They can exhibit extremely hidden multi-stability, namely the coexistence of infinite hidden attractors, rarely shown in memristive maps. Potentially, this work can be used for secure communication, such as data and image encryption.</jats:p>

<jats:title>Abstract</jats:title> <jats:p>Recently, efficiency improvement of CdTe thin film solar cell can be achieved by using new type window layer Mg<jats:sub>x</jats:sub>Zn<jats:sub>1-x</jats:sub>O (MZO). However, it is hard to achieve high efficiency as expected. In this report a comparative study was carried out between the MZO/CdTe and CdS/CdTe solar cells to investigate the factors affecting the device performance of MZO/CdTe solar cells. Efficiency loss quantified by voltage-dependent photocurrent collection efficiency (<jats:italic>η</jats:italic> <jats:sub> <jats:italic>C</jats:italic> </jats:sub>(<jats:italic>V'</jats:italic>)) was 3.89% and 1.53% for MZO/CdTe and CdS/CdTe solar cells, respectively. The higher efficiency loss for the MZO/CdTe solar cell was induced by more severe carrier recombination at the MZO/CdTe p-n junction interface and CdTe bulk region compared to the CdS/CdTe solar cell. Activation energy (<jats:italic>Ea</jats:italic>) of the reverse saturation current of the MZO/CdTe and CdS/CdTe solar cells was found to be 1.08 and 1.36 eV, respectively. These values suggested that for the CdS/CdTe solar cell the carrier recombination was dominated by bulk Shockley-Read-Hall (SRH) recombination. Whereas, for the MZO/CdTe solar cell the carrier recombination was dominated by the p-n junction interface recombination. It was found that tunneling enhanced interface recombination was also involved in carrier recombination in the MZO/CdTe solar cell. This work demonstrates the poor device performance of the MZO/CdTe solar cell was induced by more severe interface and bulk recombination than that of the CdS/CdTe device.</jats:p>

<jats:title>Abstract</jats:title> <jats:p>The Ga<jats:sub>2</jats:sub>O<jats:sub>3</jats:sub> films are deposited on the Si and quartz substrates by magnetron sputtering, and annealing. The effects of preparation parameters (such as argon-oxygen flow ratio, sputtering power, sputtering time and annealing temperature) on the growth and properties (e.g. surface morphology, crystal structure, optical and electrical properties of the films) are studied by X-ray diffractometer (XRD), scanning electron microscope (SEM), ultraviolet-visible spectrophotometer (UV-Vis). The results show that the thickness, crystallization quality and surface roughness of the <jats:italic>β</jats:italic>-Ga<jats:sub>2</jats:sub>O<jats:sub>3</jats:sub> film are influenced by the parameters. All <jats:italic>β</jats:italic>-Ga<jats:sub>2</jats:sub>O<jats:sub>3</jats:sub> films show good optical properties. Moreover, the value of bandgap increased with the enlarge of the percentage of oxygen, and decreased with the increase of sputtering power and annealing temperature, indicating that the bandgap is related to the quality of the film and affected by the number of oxygen vacancy defects. The I-V curves show that the ohmic behavior between metal and <jats:italic>β</jats:italic>-Ga<jats:sub>2</jats:sub>O<jats:sub>3</jats:sub> films is obtained at 900 ℃. These results will be helpful for the further research of <jats:italic>β</jats:italic>-Ga<jats:sub>2</jats:sub>O<jats:sub>3</jats:sub> photoelectric semiconductor.</jats:p>

<jats:title>Abstract</jats:title> <jats:p>This study proposes a novel fractional discrete-time macroeconomic system with incommensurate order. The dynamical behaviour of the proposed macroeconomic model is investigated analytically and numerically. Particularly, the zero equilibrium point stability is investigated to demonstrate that a discrete macroeconomic system exhibits chaotic behaviour. Through using bifurcation diagrams, phase attractors, maximum Lyapunov exponent and 0-1 test, we verified that chaos exists in the new model with incommensurate fractional orders. Additionally, a complexity analysis is carried out utilizing approximation entropy ($ApEn$) and $C_0$ complexity to prove that chaos exists. Finally, the main findings of this study are presented using numerical simulations.</jats:p>

<jats:title>Abstract</jats:title> <jats:p>The internal behavior of carriers in InGaAsP single-junction solar cell is investigated by using electroluminescence measurements. Two emission peaks can be observed in current-dependent electroluminescence (EL) spectra at low temperature, and carrier localization exists for both peaks under low excitation. The tendency of power index α extracted from excitation-dependent EL spectra at different temperatures implies that there is a competition between Shockley-Read-Hall recombination and Auger recombination. Auger recombination becomes dominant at high temperatures which is probably responsible for the lower current density of InGaAsP solar cell. Besides, the anomalous "S-shape" tendency with the temperature of band-edge peak position can be attributed to potential fluctuation and carrier redistribution, demonstrating delocalization, transfer, and redistribution of carriers in the continuum band-edge. Furthermore, the strong reduction of activation energy at high excitations indicates that electrons and holes escaped independently, and the faster-escaping carrier is holes.</jats:p>

<jats:title>Abstract</jats:title> <jats:p>A gated Hall-bar device is made from an epitaxially grown, free-standing InSb nanosheet on a hexagonal boron nitride (hBN) dielectric/graphite gate structure and the electron transport properties in the InSb nanosheet are studied by gate-transfer characteristic and magnetotransport measurements at low temperatures. The measurements show that the carriers in the InSb nanosheet are of electrons and the carrier density in the nanosheet can be highly efficiently tuned by the graphite gate. The mobility of the electrons in the InSb nanosheet is extracted from low-field magneotransport measurements and a value of the mobility exceeding ~18000 cm<jats:sup>2</jats:sup>V<jats:sup>-1</jats:sup>s<jats:sup>-1</jats:sup> is found. High-field magentotransport measurements show well-defined Shubnikov-de Haas (SdH) oscillations in the longitudinal resistance of the InSb nanosheet. Temperature-dependent measurements of the SdH oscillations are carried out and key transport parameters, including the electron effective mass <jats:italic>m</jats:italic> <jats:sup>*</jats:sup>~0.028 <jats:italic>m</jats:italic> <jats:sub>0</jats:sub> and the quantum lifetime <jats:italic>τ</jats:italic>~0.046 ps, in the InSb nanosheet are extracted. It is for the first time that such experimental measurements have been reported for a free-standing InSb nanosheet and the results obtained indicate that InSb nanosheet/hBN/graphite gate structures can be used to develop advanced quantum devices for novel physics studies and for quantum technology applications.</jats:p>