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<jats:title>Abstract</jats:title> <jats:p>In this paper reciprocal transformations of the space-time shifted nonlocal short pulse equations are elaborated. Covariance of dependent and independent variables involved in the reciprocal transformations is investigated. Exact solutions of the space-time shifted nonlocal short pulse equations are given in terms of double Wronskians. Realness of independent variables involved in the the reciprocal transformations is verified. Dynamics of some obtained solutions are illustrated.</jats:p>

<jats:title>Abstract</jats:title> <jats:p>The cascade glow discharge in atmospheric helium was excited by microsecond voltage pulse and pulse modulated radio frequency (RF) voltage, in which, the discharge ignition dynamics of RF discharge burst was investigated experimentally. The spatio-temporal evolution of discharge, the ignition time and optical emission intensities of plasma species of RF discharge burst are investigated under different time intervals between pulsed voltage and RF voltage in the experiment. The results show that by increasing the time interval between pulsed discharge and RF discharge burst from 5 μs to 20 μs, the ignition time of RF discharge burst is increased from 1.6 μs to 2.0 μs, and the discharge spatial profile of RF discharge in ignition phase is changed from a double-hump shape to the bell-shaped. The light emission intensity at 706 nm and 777 nm at different time intervals indicates that the RF discharge burst ignition of the depends on the amount of residual plasma species generated in the pulsed discharges.</jats:p>

<jats:title>Abstract</jats:title> <jats:p>In this work, grain boundary diffusion (GBD) process with Pr<jats:sub>80-x</jats:sub>Al<jats:sub>x</jats:sub>Cu<jats:sub>20</jats:sub> (x=0, 10, 15, 20) low melt-point alloys was applied to the commercial 42M sintered Nd-Fe-B magnets. The best coercivity enhancement of diffused magnet is the Pr<jats:sub>65</jats:sub>Al<jats:sub>15</jats:sub>Cu<jats:sub>20</jats:sub> GBD magnet, from 16.38 kOe to 22.38 kOe. Microstructural investigations indicated that increment of Al content in the diffusion source can form the continuous grain boundary (GB) phase clearly, optimizing the microstructure to enhance coercivity. The coercivity enhancement is mainly due to the formation of continuous GB phase to separate the main phase grains. The exchange decoupling between the adjacent main phase grains is enhanced after the GBD process. Meanwhile, the introduction of Al can promote Pr infiltrate into the magnet effectively which increases the diffusion rate of rare-earth elements within a certain range. This work provides a feasible method to enhance coercivity and reduce the usage of the rare-earth resource by replacing partial rare-earth element with non-rare-earth elements in the diffusion source.</jats:p>

<jats:title>Abstract</jats:title> <jats:p>We have studied the high-pressure compression behavior of molybdenum up to 60 GPa by synchrotron radial x-ray diffraction (RXRD) in a diamond anvil cell (DAC). It was found that all diffraction peaks of molybdenum undergo a split at around 27 GPa, and we believe that a phase transition from a body-centered cubic structure to a rhombohedral structure at room pressure has occurred. The slope of pressure-volume curve shows continuity before and after this phase transition, when fitting the pressure-volume curves of the body-centered cubic structure at low pressure and the rhombohedral structure at high pressure. A bulk modulus of 261.3 (2.7) GPa and a first-order derivative of the bulk modulus of 4.15 (0.14) were obtained using the nonhydrostatic compression data at the angle <jats:italic>ψ</jats:italic> = 54.7° between the diffracting plane normal and stress axis.</jats:p>

<jats:title>Abstract</jats:title> <jats:p>We report on a high-field magnetotransport of KTaO<jats:sub>3</jats:sub> single crystals, which are a promising candidate to study in the extreme quantum limit. By photocarrier doping with 360 nm light, we observe a significant positive, non-saturating, and linear magnetoresistance at low temperatures accompanied by a decreasing Hall coefficient. When cooling down to 10 K, the magnetoresistance value of KTaO<jats:sub>3</jats:sub> (100) reaches ~ 433% at a magnetic field of 12 T. Such behavior can be attributed to all electrons occupying only the lowest Landau level in the extreme quantum limit. Light inhomogeneity may also contribute to large linear magnetoresistance. This result provides insights into the novel magnetic devices based on complex materials and adds a new family of materials with positive magnetoresistance.</jats:p>

<jats:title>Abstract</jats:title> <jats:p>Threshold switching (TS) memristors can be used as artificial neurons in neuromorphic systems due to their continuous conductance modulation, scalable and energy-efficient properties. In this letter, we propose a low power artificial neuron based on the Ag/MXene/GST/Pt device with excellent TS characteristics, including a low set voltage (0.38 V) and current (200 nA), an extremely steep slope (&lt;0.1 mV/dec), and a relatively large OFF/ON ratio (&gt;10<jats:sup>3</jats:sup>). Besides, the characteristics of integrate and fire neuron that are indispensable for spiking neural networks have been experimentally demonstrated. Finally, its memristive mechanism is interpreted through the first-principles calculation depending on the electrochemical metallization effect.</jats:p>

<jats:title>Abstract</jats:title> <jats:p>The most recent spectroscopic studies of moving-single bubble sonoluminescence (MSBSL) and multi-bubble sonoluminescence (MBSL) have revealed that hydrated electrons (e$_{\texttt{aq}}^{-}$) are generated in MSBSL but absent in MBSL. To explore the mechanism this phenomenon, we numerically simulated the ionization processes in single- and multi-bubble sonoluminescence in aqueous solution of terbium chloride (TbCl$_{3}$). The results show that the maximum degree of ionization of single-bubble sonoluminescence (SBSL) is approximately 10000 times greater than that of MBSL under certain special physical parameters. The hydrated electrons (e$_{\texttt{aq}}^{-}$) formed in SBSL are far greater than those in MBSL provided these electrons are ejected from a bubble into a liquid. Therefore, the quenching of e$_{\texttt{aq}}^{-}$ to SBSL spectrum is stronger than that of the MBSL spectrum. This may be the reason that the trivalent terbium [Tb(III)] ion line intensities from SBSL in the TbCl$_{3}$ aqueous solutions with the acceptor of e$_{\texttt{aq}}^{-}$ are stronger than those of TbCl$_{3}$ aqueous solutions without the acceptor of e$_{\texttt{aq}}^{-}$, whereas the Tb(III) ion line intensities from MBSL are not variational, which is significant for exploring the mechanism behind the cavitation and sonoluminescence.</jats:p>

<jats:title>Abstract</jats:title> <jats:p>Very recently, Lee <jats:italic>et al</jats:italic>. proposed a secure quantum teleportation protocol to transfer shared quantum secret between multiple parties in a network (Phys Rev Lett 124:060501,2020). This quantum network is encoded with a maximally entangled GHZ state. In this paper, we consider a partially entangled GHZ state as the entanglement channel, where it can achieve, probabilistically, unity fidelity transfer of the state. Two kinds of strategies are given. One arises when an auxiliary particle is introduced and a general evolution at any receiver's location is then adopted. The other one involves performing a single generalized Bell-state measurement at the location of any sender. This could allow the receivers to recover the transmitted state with a certain probability, in which only the local Pauli operators are performed, instead of introducing an auxiliary particle. In addition, the successful probability is provided, which is determined by the degree of entanglement of the partially multipartite entangled state. Moreover, the proposed protocol is robust against the bit and phase flip noise.</jats:p>

<jats:title>Abstract</jats:title> <jats:p>SnO<jats:sub>2</jats:sub> is widely used as the electron transport layer (ETL) in perovskite solar cells (PSCs) due to its excellent electron mobility, low processing temperature, and low cost. And the most common way of preparing the SnO<jats:sub>2</jats:sub> ETL is spin-coating using the corresponding colloid solution. However, the spin-coated SnO<jats:sub>2</jats:sub> layer is sometimes not so compact and contains pinholes, weakening the hole blocking capability. Here, a SnO<jats:sub>2</jats:sub> thin film prepared through magnetron-sputtering was inserted between ITO and the spin-coated SnO<jats:sub>2</jats:sub> to act as an interlayer. This strategy can combine the advantages of efficient electron extraction and hole blocking due to the high compactness of the sputtered film and the excellent electronic property of the spin-coated SnO<jats:sub>2</jats:sub>. Therefore, the recombination of photo-generated carriers at the interface is significantly reduced. As a result, the semitransparent perovskite solar cells (with a bandgap of 1.73 eV) based on this double-layered SnO<jats:sub>2</jats:sub> demonstrate a maximum efficiency of 17.70% (stabilized at 17.04%) with negligible hysteresis. Moreover, the shelf stability of the device is also significantly improved, maintaining 95% of the initial efficiency after 800-hours of aging.</jats:p>

<jats:title>Abstract</jats:title> <jats:p>Development of p-type transparent conducting thin films is tireless due to the trade-off issue between optical transparency and conductivity. The rarely concerned low normal state resistance makes Bi-based superconducting cuprates as potential hole-type transparent conductors, which have been realized in Bi$_2$Sr$_2$CaCu$_2$O$_y$ thin films. In this study, epitaxial superconducting Bi$_2$Sr$_2$CuO$_y$ and Bi$_2$Sr$_{1.8}$Nd$_{0.2}$CuO$_y$ thin films with superior normal state conductivity are proposed as p-type transparent conductors. It is found that the Bi$_2$Sr$_{1.8}$Nd$_{0.2}$CuO$_y$ thin film with 15 nm thick shows an average visible transmittance of 65% and room temperature sheet resistance of 650 $\Omega/sq$. The results further demonstrate that Bi-based cuprate superconductors can be regarded as potential p-type transparent conductors for future optoelectronic applications.</jats:p>