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<jats:p>The role of the microalloying process in relaxation behavior and crystallization evolution of Zr<jats:sub>20</jats:sub>Cu<jats:sub>20</jats:sub>Ni<jats:sub>20</jats:sub>Ti<jats:sub>20</jats:sub>Hf<jats:sub>20</jats:sub> high entropy bulk metallic glass (HEBMG) was investigated. We selected Al and Nb elements as minor elements, which led to the negative and positive effects on the heat of mixing in the master HEBMG composition, respectively. According to the results, both elements intensified <jats:italic>β</jats:italic> relaxation in the structure; however, <jats:italic>α</jats:italic> relaxation remained stable. By using different frequencies in dynamic mechanical analysis, it was revealed that the activation energy of <jats:italic>β</jats:italic> relaxation for the Nb-added sample was much higher, which was due to the creation of significant structural heterogeneity under the microalloying process. Moreover, it was found that Nb addition led to a diversity in crystallization stages at the supercooled liquid region. It was suggested that the severe structural heterogeneity in the Nb-added sample provided multiple energy-level sites in the structure for enhancing the crystallization stages.</jats:p>

<jats:p>Floquet theorem is widely used in the light-driven systems. But many 2D-materials models under the radiation are investigated with the high-frequency approximation, which may not be suitable for the practical experiment. In this work, we employ the non-perturbative Floquet method to strictly investigate the photo-induced topological phase transitions and edge states properties of graphene nanoribbons under the light irradiation of different frequencies (including both low and high frequencies). By analyzing the Floquet energy bands of ribbon and bulk graphene, we find the cause of the phase transitions and its relation with edge states. Besides, we also find the size effect of the graphene nanoribbon on the band gap and edge states in the presence of the light.</jats:p>

<jats:p>Motivated by recent advances in orbitally tuned Feshbach resonance experiments, we analyze the ground-state phase diagram and related low-energy excitation spectra of a d-wave interacting Bose gas. A two-channel model with d-wave symmetric interactions and background s-wave interactions is adopted to characterize the gas. The ground state is found to have three interesting superfluid phases: atomic, molecular, and atomic–molecular. In great contrast to what was previously known about the p-wave case, the atomic superfluid is found to be momentum-independent for the d-wave case discussed here. The Bogoliubov spectra above each superfluid phase are obtained both analytically and numerically.</jats:p>

<jats:p>One-dimensional nanowire is an important candidate for lead-halide perovskite-based photonic detectors and solar cells. Its surface population, diameter, and growth direction, <jats:italic>etc.</jats:italic>, are critical for device performance. In this research, we carried out a detailed study on electron transfer process at the interface of nanowire CH<jats:sub>3</jats:sub>NH<jats:sub>3</jats:sub>PbI<jats:sub>3</jats:sub>(N-MAPbI<jats:sub>3</jats:sub>)/Phenyl C61 butyric acid methyl-ester synonym (PCBM), as well as the interface of compact CH<jats:sub>3</jats:sub>NH<jats:sub>3</jats:sub>PbI<jats:sub>3</jats:sub>(C-MAPbI<jats:sub>3</jats:sub>)/PCBM by transient absorption spectroscopy. By comparing the carrier recombination dynamics of N-MAPbI<jats:sub>3</jats:sub>, N-MAPbI<jats:sub>3</jats:sub>/PCBM, C-MAPbI<jats:sub>3</jats:sub>, and C-MAPbI<jats:sub>3</jats:sub>/PCBM from picosecond (ps) to hundred nanosecond (ns) time scale, it is demonstrated that electron transfer at N-MAPbI<jats:sub>3</jats:sub>/PCBM interface is less efficient than that at C-MAPbI<jats:sub>3</jats:sub>/PCBM interface. In addition, electron transfer efficiency at C-MAPbI<jats:sub>3</jats:sub>/PCBM interface was found to be excitation density-dependent, and it reduces with photo-generation carrier concentration increasing in a range from 1.0 × 10<jats:sup>18</jats:sup> cm<jats:sup>−3</jats:sup>–4.0 × 10<jats:sup>18</jats:sup> cm<jats:sup>−3</jats:sup>. Hot electron transfer, which leads to acceleration of electron transfer between the interfaces, was also visualized as carrier concentration increases from 1.0 × 10<jats:sup>18</jats:sup> cm<jats:sup>−3</jats:sup>–2.2 × 10<jats:sup>18</jats:sup> cm<jats:sup>−3</jats:sup>.</jats:p>

<jats:p>We study the Kondo screening of a spin-1/2 magnetic impurity in the hybrid nodal line semimetals (NLSMs) and the type-II NLSMs by using the variational method. We mainly study the binding energy and the spin–spin correlation between magnetic impurity and conduction electrons. We find that in both the hybrid and type-II cases, the density of states (DOS) is always finite, so the impurity and the conduction electrons always form bound states, and the bound state is more easily formed when the DOS is large. Meanwhile, due to the unique dispersion relation and the spin–orbit couplings in the NLSMs, the spatial spin–spin correlation components show very interesting features. Most saliently, various components of the spatial spin–spin correlation function decay with 1/<jats:italic>r</jats:italic> <jats:sup>2</jats:sup> in the hybrid NLSMs, while they follow 1/<jats:italic>r</jats:italic> <jats:sup>3</jats:sup> decay in the type-II NLSMs. This property is mainly caused by the special band structures in the NLSMs, and it can work as a fingerprint to distinguish the two types of NLSMs.</jats:p>

<jats:p>Single-atom catalysts (SACs) have attracted great interest due to their significant roles played in applications of environmental protection, energy conversion, energy storage, and so on. Using first-principles calculations with dispersion-correction, we investigated the structural stability and catalytic activity of Co implanted CN sheet towards CO oxidation. The adsorption energy of CO and O<jats:sub>2</jats:sub> on the catalysts Co@CN and 2Co@CN are close, thus preventing CO poisoning. Among three possible CO oxidation mechanisms, termolecular Eley-Rideal is the most appropriate reaction path, and the corresponding rate-limiting reaction barriers of the two systems are 0.42 eV and 0.38 eV, respectively.</jats:p>

<jats:p>We investigate a high sensitive chiral molecule detector based on Goos–Hanchen shift (<jats:italic>S</jats:italic>) in Kretschmann configuration involving chiral tri (diethylene glycol monobutyl) citrates (TDBCs). Fresnel equations and the stationary phase method are employed to calculate <jats:italic>S</jats:italic>. Due to the interaction between surface plasmon polaritons and chiral TDBCs, <jats:italic>S</jats:italic> with chiral TDBCs are amplified at near the resonant wavelengths of chiral TDBCs. Our calculation results show that although the difference between the resonant wavelengths of left and right TDBCs is 4.5 nm, the positions of the largest <jats:italic>S</jats:italic> for the structures with left TDBCs and right TDBCs do not overlap. <jats:italic>S</jats:italic> reaches 400 times (or 200 times) the incident wavelength around the resonant wavelength of left TDBCs (or right TDBCs). The difference of <jats:italic>S</jats:italic> with chiral TDBCs (Δ <jats:italic>S</jats:italic>) can reach 400 times or 200 times the incident wavelength in certain conditions, which can be directly observed in experiments. Left TDBCs and right TDBCs are easily distinguished. There is an optimal thickness of the metal film to realize the largest difference of <jats:italic>S</jats:italic> between Kretschmann configurations with left TDBCs and right TDBCs. Furthermore, we discuss the oscillator strength <jats:italic>f</jats:italic>, which is mainly determined by TDBC concentration. We find that our proposed detector is quite sensitive with <jats:italic>f</jats:italic>. By changing <jats:italic>f</jats:italic> from 0.008 to 0.014 with the step of 0.002, the change of Δ <jats:italic>S</jats:italic> is no less than five times the incident wavelength (2.9 μm). Our proposed structure is very sensitive to the chirality and the concentration of TDBCs and has potential applications in distinguishing the chirality detector.</jats:p>

<jats:p>The ultra-wide bandgap semiconductor <jats:italic>β</jats:italic> gallium oxide (<jats:italic>β</jats:italic>-Ga<jats:sub>2</jats:sub>O<jats:sub>3</jats:sub>) gives promise to low conduction loss and high power for electronic devices. However, due to the natural poor thermal conductivity of <jats:italic>β</jats:italic>-Ga<jats:sub>2</jats:sub>O<jats:sub>3</jats:sub>, their power devices suffer from serious self-heating effect. To overcome this problem, we emphasize on the effect of device structure on peak temperature in <jats:italic>β</jats:italic>-Ga<jats:sub>2</jats:sub>O<jats:sub>3</jats:sub> Schottky barrier diodes (SBDs) using TCAD simulation and experiment. The SBD topologies including crystal orientation of <jats:italic>β</jats:italic>-Ga<jats:sub>2</jats:sub>O<jats:sub>3</jats:sub>, work function of Schottky metal, anode area, and thickness, were simulated in TCAD, showing that the thickness of <jats:italic>β</jats:italic>-Ga<jats:sub>2</jats:sub>O<jats:sub>3</jats:sub> plays a key role in reducing the peak temperature of diodes. Hence, we fabricated <jats:italic>β</jats:italic>-Ga<jats:sub>2</jats:sub>O<jats:sub>3</jats:sub> SBDs with three different thickness epitaxial layers and five different thickness substrates. The surface temperature of the diodes was measured using an infrared thermal imaging camera. The experimental results are consistent with the simulation results. Thus, our results provide a new thermal management strategy for high power <jats:italic>β</jats:italic>-Ga<jats:sub>2</jats:sub>O<jats:sub>3</jats:sub> diode.</jats:p>

<jats:p>A novel terminal-optimized triple RESURF LDMOS (TOTR-LDMOS) is proposed and verified in a 0.25-μm bipolar-CMOS-DMOS (BCD) process. By introducing a low concentration region to the terminal region, the surface electric field of the TOTR-LDMOS decreases, helping to improve the breakdown voltage (<jats:italic>BV</jats:italic>) and electrostatic discharge (ESD) robustness. Both traditional LDMOS and TOTR-LDMOS are fabricated and investigated by transmission line pulse (TLP) tests, direct current (DC) tests, and TCAD simulations. The results show that comparing with the traditional LDMOS, the <jats:italic>BV</jats:italic> of the TOTR-LDMOS increases from 755 V to 817 V without affecting the specific on-resistance (<jats:italic>R</jats:italic> <jats:sub>on,sp</jats:sub>) of 6.99 Ω⋅mm<jats:sup>2</jats:sup>. Meanwhile, the ESD robustness of the TOTR-LDMOS increases by 147%. The TOTR-LDMOS exhibits an excellent performance among the present 700-V LDMOS devices.</jats:p>

<jats:p>We investigate the Hall effects of quadratic band crossing (QBC) fermions in a square optical lattice with spin–orbit coupling and orbital Zeeman term. We find that the orbital Zeeman term and shaking play critical roles in the systems, which can drive a topological transition from spin Hall phases to anomalous Hall phase with nonvanishing (spin) Chern numbers. Due to the interplay among the orbital Zeeman term, spin–orbit coupling, and the shaking, the phase diagram of the system exhibits rich phases, which are characterized by Chern number.</jats:p>