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<jats:p>In this paper, we present a highly efficient structure determination pipeline software suite (X<jats:sup>2</jats:sup>DF) that is based on the “Parameter space screening” method, by combining the popular crystallographic structure determination programs and high-performance parallel computing. The phasing method employed in X<jats:sup>2</jats:sup>DF is based on the single-wavelength anomalous diffraction (SAD) theory. In the X<jats:sup>2</jats:sup>DF, the choice of crystallographic software, the input parameters to this software and the results display layout, are all parameters which users can select and screen automatically. Users may submit multiple structure determination jobs each time, and each job uses a slightly different set of input parameters or programs. Upon completion, the results of the calculation performed can be displayed, harvested, and analyzed by using the graphical user interface (GUI) of the system. We have applied the X<jats:sup>2</jats:sup>DF successfully to many cases including the cases that the structure solutions fail to be yielded by using manual approaches.</jats:p>

<jats:p>Polycrystalline samples of La<jats:sub>2</jats:sub>Zr<jats:sub>2</jats:sub>O<jats:sub>7</jats:sub> pyrochlore are irradiated by different energetic heavy ions to investigate the dependence of the vibrational mode variations on the irradiation parameters. The applied electronic energy loss (d<jats:italic>E</jats:italic>/d<jats:italic>x</jats:italic>)<jats:sub>e</jats:sub> increases from about 5.2 keV/nm to 39.6 keV/nm. The ion fluence ranges from 1 × 10<jats:sup>11</jats:sup> ions/cm<jats:sup>2</jats:sup> to 6 × 10<jats:sup>15</jats:sup> ions/cm<jats:sup>2</jats:sup>. Vibrational modes of irradiated pyrochlore are analyzed by using Raman spectrum. Infrared active modes F<jats:sub>1u</jats:sub> at 192, 308, and 651 cm<jats:sup>−1</jats:sup> appear in Raman spectra, and the F<jats:sub>2g</jats:sub> band at 265 cm<jats:sup>−1</jats:sup> rises up due to the irradiation by 200-MeV Kr ions with (d<jats:italic>E</jats:italic>/d<jats:italic>x</jats:italic>)<jats:sub>e</jats:sub> of 16.0 keV/nm. Differently, for the pyrochlore irradiated by 1750-MeV Bi ions with (d<jats:italic>E</jats:italic>/d<jats:italic>x</jats:italic>)<jats:sub>e</jats:sub> of 39.6 keV/nm, in spite of the appearance of infrared active mode F<jats:sub>1u</jats:sub> 651 cm<jats:sup>−1</jats:sup>, the amorphous structure occurs according to the vibrational mode variations of pyrochlore irradiated at higher ion fluences. Amorphous tracks are observed in the samples, which confirm the occurrence of pyrochlore–amorphous transition in pyrochlore irradiated with (d<jats:italic>E</jats:italic>/d<jats:italic>x</jats:italic>)<jats:sub>e</jats:sub> of 39.6 keV/nm.</jats:p>

<jats:p>A one-dimensional (1D) self-organized array composed of dislocation and anti-dislocation is analytically investigated in the frame of Peierls theory. From the exact solution of the Peierls equation, it is found that there exists strong neutralizing effect that makes the Burgers vector of each individual dislocation in the equilibrium array smaller than that of an isolated dislocation. This neutralizing effect is not negligible even though dislocations are well separated. For example, when the distance between the dislocation and the anti-dislocation is as large as ten times of the dislocation width, the actual Burgers vector is only about 80 % of an isolated dislocation. The neutralizing effect originates physically from the power-law asymptotic behavior that enables two dislocations interfere even though they are well separated.</jats:p>

<jats:p>We employ multiple order parameters to analyze the local structure of liquid water obtained from all-atom simulations, and accordingly identify three types of molecules in water. In addition to the well-known low-density-liquid and high-density-liquid molecules, the newly identified third type possesses an ultra-high density and over-coordinated H-bonds. The existence of this third type decreases the probability of transition of high-density-liquid molecules to low-density-liquid molecules and increases the probability of the reverse one.</jats:p>

<jats:p>Using first-principles calculations in the generalized gradient approximation plus on-site Coulomb interaction (GGA+<jats:italic>U</jats:italic>) scheme, the effects of internal structural parameters <jats:italic>x</jats:italic> and <jats:italic>U</jats:italic> on the electronic structure of YbB<jats:sub>6</jats:sub> are investigated. The results show that the band gap of YbB<jats:sub>6</jats:sub> increases with <jats:italic>x</jats:italic> increasing, and does not change with <jats:italic>U</jats:italic>. It not only illustrates the influence of internal structural parameter <jats:italic>x</jats:italic> on band gap, but also explains the discrepancy between the previous experimental result and the theoretical prediction. In addition, the electronic structure and density of states reveal that there exist the interactions between B atoms in different cages, and that a small band gap can form around the Fermi level (<jats:italic>E</jats:italic> <jats:sub>F</jats:sub>). The present work plays a leading role in ascertaining the relation between crystal structure and electronic property for the further analysis of its topological properties.</jats:p>

<jats:p>Reflection and transmission are two behaviors of wave propagating to an interface. The immiscible binary mixtures of Bose–Einstein condensates can form the symmetry-breaking state, in which the domain wall on the center can serve as the interface. In this study, we explore in detail the propagation of a dark soliton interacting with the domain wall in the harmonic trap. We find that the low-energy dark soliton is easy to form the transmission and the high-energy dark soliton trends to reflect from the domain wall. Both reflection and transmission of dark soliton on the domain wall induce the sound radiation. But the sound radiation in the reflection derives from the collective oscillation of condensates, and it in the transmission comes not only from the collective oscillation, but also from the condensate filling in the dark soliton.</jats:p>

<jats:p>The polarization effect introduced by electric field deformation is the most important bottleneck of CdZnTe detector in x-ray imaging. Currently, most of studies focus on electric field deformation caused by trapped carriers; the perturbation of electric field due to drifting carriers has been rarely reported. In this study, the effect of transient space–charge perturbation on carrier transport in a CdZnTe semiconductor is evaluated by using the laser-beam-induced current (LBIC) technique. Cusps appear in the current curves of CdZnTe detectors with different carrier transport performances under intense excitation, indicating the deformation of electric field. The current signals under different excitations are compared. The results suggest that with the increase of excitation, the amplitude of cusp increases and the electron transient time gradually decreases. The distortion in electric field is independent of carrier transport performance of detector. Transient space–charge perturbation is responsible for the pulse shape and affects the carrier transport process.</jats:p>

<jats:p>Previous studies presented the phase diagram induced by the disorder existing separately either in the higher-order topological states or in the topological trivial states, respectively. However, the influence of disorder on the system with the coexistence of the higher-order topological states and other traditional topological states has not been investigated. In this paper, we investigate the disorder induced phase transition in the magnetic higher-order topological insulator. By using the convolutional neural network and non-commutative geometry methods, two independent phase diagrams are calculated. With the comparison between these two diagrams, a topological transition from the normal insulator to the Chern insulator is confirmed. Furthermore, the network based on eigenstate wavefunction studies also presents a transition between the higher-order topological insulator and the Chern insulator.</jats:p>

<jats:p>We systematically studied surface plasmons reflection by graphene wrinkles with different heights on SiC substrate. Combined with numerical simulation, we found that the geometry corrugation of a few nanometer height wrinkle alone does not causes a reflection of graphene plasmons. Instead, the separated wrinkle from substrate exhibits a nonlinear spatial Fermi energy distribution along the wrinkle, which acts as a heterojunction. Therefor a higher graphene wrinkle induces a stronger damped region when propagating graphene surface plasmons encounter the wrinkle and get reflected.</jats:p>

<jats:p>Both long-term environmental durability and high reflectance of protected-Al mirrors are of great importance for developing the optical instruments in the vacuum ultraviolet (VUV) applications. In this paper, the dependence of spectral property and environmental durability of MgF<jats:sub>2</jats:sub> over-coated Al mirrors using a 3-step method on deposition temperature of the outermost MgF<jats:sub>2</jats:sub> layer are investigated in detail. Optics (reflectance), structure (surface morphology and crystalline), and environmental durability (humidity test) are characterized and discussed. The results show that both optical and moisture-resistant properties of MgF<jats:sub>2</jats:sub> over-coated Al mirrors are dependent on MgF<jats:sub>2</jats:sub> deposition temperature, and the optimal deposition temperature for the outermost MgF<jats:sub>2</jats:sub> layer should be between 250 °C and 300 °C for MgF<jats:sub>2</jats:sub> over-coated Al mirrors to have both reasonably high reflectance in the VUV spectral range and high moisture resistance for long lifetime applications.</jats:p>