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<jats:p>We investigate systematically the effects of the inter-particle attraction on the structure and dynamical behaviors of glass-forming liquids via molecular dynamics simulations. We find that the inter-particle attraction does not influence the structure, but greatly affects the dynamics and dynamical heterogeneity of the system. After the system changes from a purely repulsive glass-forming liquid to an attractive one, the dynamics slows down and the dynamical heterogeneity becomes greater, which is found interestingly to be associated with larger cooperative rearrangement regions (CRRs). Additionally, the structures of CRRs are observed to be compact in attractive glass-forming liquids but string-like in purely repulsive ones. Our findings constitute an important contribution to the ongoing study of the role of attractions in properties of glasses and glass-forming liquids.</jats:p>

<jats:p>The prospect of <jats:italic>α</jats:italic>-Ga<jats:sub>2</jats:sub>O<jats:sub>3</jats:sub> in optical and electrical devices application is fascinating. In order to obtain better performance, Ge and F elements with similar electronegativity and atomic size are selected as dopants. Based on density functional theory (DFT), we systematically research the electronic structure and optical properties of doped <jats:italic>α</jats:italic>-Ga<jats:sub>2</jats:sub>O<jats:sub>3</jats:sub> by GGA+<jats:italic>U</jats:italic> calculation method. The results show that Ge atoms and F atoms are effective n-type dopants. For Ge-doped <jats:italic>α</jats:italic>-Ga<jats:sub>2</jats:sub>O<jats:sub>3</jats:sub>, it is probably obtained under O-poor conditions. However, for F-doped <jats:italic>α</jats:italic>-Ga<jats:sub>2</jats:sub>O<jats:sub>3</jats:sub>, it is probably obtained under O-rich conditions. The doping system of F element is more stable due to the lower formation energy. In this investigation, it is found that two kinds of doping can reduce the <jats:italic>α</jats:italic>-Ga<jats:sub>2</jats:sub>O<jats:sub>3</jats:sub> band gap and improve the conductivity. What is more, it is observed that the absorption edge after doping has a blue shift and causes certain absorption effect on the visible region. Through the whole scale of comparison, Ge doping is more suitable for the application of transmittance materials, yet F doping is more appropriate for the application of deep ultraviolet devices. We expect that our research can provide guidance and reference for preparation of <jats:italic>α</jats:italic>-Ga<jats:sub>2</jats:sub>O<jats:sub>3</jats:sub> thin films and photoelectric devices.</jats:p>

<jats:p>In marginally jammed solids confined by walls, we calculate the particle and ensemble averaged value of an order parameter, 〈<jats:italic>Ψ</jats:italic>(<jats:italic>r</jats:italic>)〉, as a function of the distance to the wall, <jats:italic>r</jats:italic>. Being a microscopic indicator of structural disorder and particle mobility in solids, <jats:italic>Ψ</jats:italic> is by definition the response of the mean square particle displacement to the increase of temperature in the harmonic approximation and can be directly calculated from the normal modes of vibration of the zero-temperature solids. We find that, in confined jammed solids, 〈<jats:italic>Ψ</jats:italic>(<jats:italic>r</jats:italic>)〉 curves at different pressures can collapse onto the same master curve following a scaling function, indicating the criticality of the jamming transition. The scaling collapse suggests a diverging length scale and marginal instability at the jamming transition, which should be accessible to sophisticatedly designed experiments. Moreover, 〈<jats:italic>Ψ</jats:italic>(<jats:italic>r</jats:italic>)〉 is found to be significantly suppressed when approaching the wall and anisotropic in directions perpendicular and parallel to the wall. This finding can be applied to understand the <jats:italic>r</jats:italic>-dependence and anisotropy of the structural relaxation in confined supercooled liquids, providing another example of understanding or predicting behaviors of supercooled liquids from the perspective of the zero-temperature amorphous solids.</jats:p>

<jats:p>Exploring the mechanism of interfacial thermal transport and reducing the interfacial thermal resistance are of great importance for thermal management and modulation. Herein, the interfacial thermal resistance between overlapped graphene nanoribbons is largely reduced by adding bonded carbon chains as shown by molecular dynamics simulations. And the analytical model (phonon weak couplings model, PWCM) is utilized to analyze and explain the two-dimensional thermal transport mechanism at the cross-interface. An order of magnitude reduction of the interfacial thermal resistance is found as the graphene nanoribbons are bonded by just one carbon chain. Interestingly, the decreasing rate of the interfacial thermal resistance slows down gradually with the increasing number of carbon chains, which can be explained by the proposed theoretical relationship based on analytical model. Moreover, by the comparison of PWCM and the traditional simplified model, the accuracy of PWCM is demonstrated in the overlapped graphene nanoribbons. This work provides a new way to improve the interfacial thermal transport and reveal the essential mechanism for low-dimensional materials applied in thermal management.</jats:p>

<jats:p>Based on first-principles calculations, Boltzmann transport equation and semiclassical analysis, we conduct a detailed study on the lattice thermal conductivity <jats:italic>κ</jats:italic> <jats:sub>L</jats:sub>, Seebeck coefficient <jats:italic>S</jats:italic>, electrical conductivity <jats:italic>σ</jats:italic>, power factor <jats:italic>S</jats:italic> <jats:sup>2</jats:sup> <jats:italic>σ</jats:italic> and dimensionless figure of merit, <jats:italic>zT</jats:italic>, for K<jats:sub>3</jats:sub>IO. It is found that K<jats:sub>3</jats:sub>IO exhibits relatively low lattice thermal conductivity of 0.93 W⋅m<jats:sup>−1</jats:sup>⋅K<jats:sup>−1</jats:sup> at 300 K, which is lower than the value 1.26 W⋅m<jats:sup>−1</jats:sup>⋅K<jats:sup>−1</jats:sup> of the classical TE material PbTe. This is due to the smaller phonon group velocity <jats:italic>ν</jats:italic> <jats:sub>g</jats:sub> and smaller relaxation time <jats:italic>τ<jats:sub>λ</jats:sub> </jats:italic>. The low lattice thermal conductivity can lead to excellent thermoelectric properties. Thus maximum <jats:italic>zT</jats:italic> of 2.87 is obtained at 700 K, and the <jats:italic>zT</jats:italic> = 0.41 at 300 K indicate that K<jats:sub>3</jats:sub>IO is a potential excellent room temperature TE material. Our research on K<jats:sub>3</jats:sub>IO shows that it has excellent thermoelectric properties, and it is a promising candidate for applications in fields in terms of thermoelectricity.</jats:p>

<jats:p>Localization, one of the basic phenomena for wave transport, has been demonstrated to be an effective strategy to manipulate electronic, photonic, and acoustic properties of materials. Due to the wave nature of phonons, the tuning of thermal properties through phonon localization would also be expected, which is beneficial to many applications such as thermoelectrics, electronics, and phononics. With the development of nanotechnology, nanostructures with characteristic length about ten nanometers can give rise to phonon localization, which has attracted considerable attention in recent years. This review aims to summarize recent advances with theoretical, simulative, and experimental studies toward understanding, prediction, and utilization of phonon localization in disordered nanostructures, focuses on the effect of phonon localization on thermal conductivity. Based on previous researches, perspectives regarding further researches to clarify this hectic-investigated and immature topic and its exact effect on thermal transport are given.</jats:p>

<jats:p>Borophene allotropes have many unique physical properties due to their polymorphism and similarity between boron and carbon. In this work, based on the density functional theory and phonon Boltzmann transport equation, we investigate the lattice thermal conductivity <jats:italic>κ</jats:italic> of both <jats:italic>β</jats:italic> <jats:sub>12</jats:sub> and <jats:italic>χ</jats:italic> <jats:sub>3</jats:sub> borophene. Interestingly, these two allotropes with similar lattice structures have completely different thermal transport properties. <jats:italic>β</jats:italic> <jats:sub>12</jats:sub> borophene has almost isotropic <jats:italic>κ</jats:italic> around 90 W/(m⋅K) at 300 K, while <jats:italic>κ</jats:italic> of <jats:italic>χ</jats:italic> <jats:sub>3</jats:sub> borophene is much larger and highly anisotropic. The room temperature <jats:italic>κ</jats:italic> of <jats:italic>χ</jats:italic> <jats:sub>3</jats:sub> borophene along the armchair direction is 512 W/(m⋅K), which is comparable to that of hexagonal boron nitride but much higher than most of the two-dimensional materials. The physical mechanisms responsible for such distinct thermal transport behavior are discussed based on the spectral phonon analysis. More interestingly, we uncover a unique one-dimensional transport feature of transverse acoustic phonon in <jats:italic>χ</jats:italic> <jats:sub>3</jats:sub> borophene along the armchair direction, which results in a boost of phonon relaxation time and thus leads to the significant anisotropy and ultrahigh thermal conductivity in <jats:italic>χ</jats:italic> <jats:sub>3</jats:sub> borophene. Our study suggests that <jats:italic>χ</jats:italic> <jats:sub>3</jats:sub> borophene may have promising application in heat dissipation, and also provides novel insights for enhancing the thermal transport in two-dimensional systems.</jats:p>

<jats:p>The evaporation of water is essential in the macroscopic world. Recent researches show that, on solid surfaces, the evaporation of nanoscale water is quite different from that on bulk water surfaces. In this review, we show the theoretical progress in the study of nanoscale water evaporation on various solid surfaces: the evaporation rate of nanoscale water does not show a monotonic decrease when the solid surface changes from hydrophobic to hydrophilic; the evaporation of nanoscale water on hydrophobic–hydrophilic patterned surfaces is unexpectedly faster than that on uniform surface; the evaporation of nanoscale water on patterned graphene oxide is faster than that on homogeneous one; how temperature affects the evaporation of nanoscale water on solid surface; how ions affect the evaporation of nanoscale water on graphene oxide.</jats:p>

<jats:p>The temperature-dependent Gilbert damping in Co<jats:sub>2</jats:sub>FeAl thin film grown on a Pb(Mg<jats:sub>1/3</jats:sub>Nb<jats:sub>2/3</jats:sub>)O<jats:sub>3</jats:sub>-30%PbTiO<jats:sub>3</jats:sub> substrate is investigated by the systematic measurement of physical property measurement system (PPMS) on a series of samples with different substrate temperatures. Varying the substrate temperatures from 350 °C to 500 °C, the B2 ordering degrees of Co<jats:sub>2</jats:sub>FeAl thin films increase, which can lead the Gilbert damping to decrease, indicated by the field-sweep in-plane PPMS measurements. In addition, the measurement result of PPMS demonstrates that the Gilbert damping decreases first with measurement temperature decreasing down to about 150 K, then increases at a measurement temperature of ∼ 50 K, and decreases again with the measurement temperature decreasing. There are two independent damping manners, namely bulk damping and surface damping, which contribute to the Gilbert damping. Moreover, the observed peak of Gilbert damping at ∼ 50 K can be attributed to the spin re-orientation transition at the Co<jats:sub>2</jats:sub>FeAl surface, which is similar to the result of the effective magnetization as a function of measurement temperature. The result presents the evidence for further studying the Gilbert damping in Co<jats:sub>2</jats:sub>FeAl thin film.</jats:p>

<jats:p>The impact of supercritical CO<jats:sub>2</jats:sub>/H<jats:sub>2</jats:sub>O technology on the threshold-voltage instability of AlGaN/GaN metal-insulator semiconductor high-electron-mobility transistors (MIS-HEMTs) is investigated. The MIS-HEMTs were placed in a supercritical fluid system chamber at 150 °C for 3 h. The chamber was injected with CO<jats:sub>2</jats:sub> and H<jats:sub>2</jats:sub>O at pressure of 3000 psi (1 psi ≈ 6.895 kPa). Supercritical H<jats:sub>2</jats:sub>O fluid has the characteristics of liquid H<jats:sub>2</jats:sub>O and gaseous H<jats:sub>2</jats:sub>O at the same time, that is, high penetration and high solubility. In addition, OH<jats:sup>−</jats:sup> produced by ionization of H<jats:sub>2</jats:sub>O can fill the nitrogen vacancy near the Si<jats:sub>3</jats:sub>N<jats:sub>4</jats:sub>/GaN/AlGaN interface caused by high temperature process. After supercritical CO<jats:sub>2</jats:sub>/H<jats:sub>2</jats:sub>O treatment, the threshold voltage shift is reduced from 1 V to 0.3 V. The result shows that the threshold voltage shift of MIS-HEMTs could be suppressed by supercritical CO<jats:sub>2</jats:sub>/H<jats:sub>2</jats:sub>O treatment.</jats:p>