Modern Physics Letters B

Dispersing three-dimensional (3D) nanoparticles as the filler into a polymeric component is known to significantly improve the physicochemical properties of the materials and makes them attractive for industrial applications. There are two main contributions to the underlying enhancement mechanism of polymer nanocomposites (PNCs). The first contribution is linked to the interfacial effect, originating from the interaction between polymer and nanoparticles. The packing density, conformation and orientation of adsorbed chains are significantly altered, which results in an interfacial region with different properties from the bulk. The second contribution is attributed to the spatial effect, introduced by confining polymer chains in a restricted space between/among nanoparticles. These two effects are often correlated. The characteristic behavior of polymer chains confined by nanoparticles has already shown to be quite complicated and hence interesting as compared with that of pure polymers. The broad range of influencing factors including the size, content and surface chemistry of nanoparticles as well as the molecular weight and chain ends of polymers were discussed in this review. The controversial issues such as the segmental dynamics at interface, interfacial architecture and the extent of its impact on the bulk phase were summarized, wishing to produce further understanding of PNCs.

ICIO data have proven itself to be a reliable source for the analysis of economic globalization, with which sectors all over the world could be constructed into a sophisticated GVC, bringing the advantages of simultaneous study on international and domestic economies in detail as a holistic network. This paper uses OECD–WTO TiVA data to set up GIVCN-TiVA networks as the general analytical framework, depicting the transferring process of intermediate goods among sectors of various countries/regions. Secondly, the conception of brokerage roles in SNA has been adopted to redefine sector’s function while linkage exists between its upstream providers and downstream consumers, referred to as “Trade Brokerage Property”, as well as to quantify the ratio of each types of the roles. Thirdly, a set of simulations have been defined to testify the contribution that different TBPs incur to the robustness of global economic system. Finally, analyses on TBPs and NTBPs have been carried out in the levels of industry and country/region, respectively.

In this paper, kappa distribution of electronic energy is discussed for non-Maxwellian distribution. Taking silicon III 189.2 nm line in solar atmospheric plasma as an example, we discuss the kappa distribution and the Maxwellian distribution when temperature varies from $10^{4.0}$ K to $10^{6.0}$ K, and we calculate the averaged collision strengths of the kappa distribution and the Maxwellian distribution. Results indicate that the kappa distribution is close to the Maxwellian distribution with the increase of parameter $\kappa$, and the difference of the averaged collision strength between the kappa distribution and the Maxwellian distribution is not very large in the higher temperature region from $10^{4.4}$ K to $10^{6.0}$ K, while that is large in the lower temperature region from $10^{4.0}$ K to $10^{4.6}$ K. This discussion will be significant in study of plasma quantitatively.

We investigate decoherence of quantum superpositions induced by gravitational time dilation and spontaneous emission between two atomic levels. It has been shown that gravitational time dilation can be a universal decoherence source by Pikovski et al. Here, we consider the decoherence induced by the gravitational time dilation only in the situation of spontaneous emission. We obtain the analytical results of the coherence of particle’s position state. Then, we obtain that the coherence of particle’s position state depends on reference frame because the time dilation changes the distinguishability of emitted photons from two positions of particle in different reference frames. For observing the decoherence effect induced by the gravitational time dilation, time-delayed feedback can be utilized to increase the decoherence of particle’s superposition state.

This paper analyzes the properties of the two-component Bose–Einstein condensates (BECs) with long-range monopolar interaction by means of Thomas–Fermi approximation (TFA). The effects of long-range monopolar interaction, inter-component short-range s-wave scattering, and particle numbers on the density profiles and phase separation of BECs are investigated. It is shown that atoms with the small intra-component s-wave scattering length are squeezed out when the monopolar interaction of these atoms is not large enough, and the density profile will be compressed when corresponding monopolar interaction is increased. Effective zero interaction point that the s-wave scattering repulsive interaction is neutralized by monopolar attractive interaction, is found. Varying of particle numbers will cause the transformation between phase separation and faint phase separation (or mixture).

The transport properties in ultrasmall single-wall carbon nanotubes (SWCNTs) under tensile strain have been theoretically investigated. The regular negative differential resistance (NDR) induced by the strain undergoes a process from enhancement to weakening in the zigzag (3,0) SWCNT. The NDR achieves maximum with applying 4% tensile strain. Compared to the case of (3,0) SWCNT, that NDR cannot be manipulated by applying strain clearly in (4,0) and (5,0) ultrasmall SWCNTs with tensile strain lower than 10%. It proposes this strain-induced NDR effect to demonstrate the possibility of finding potential applications in SWCNT-based NDR nanodevices such as in memory devices, oscillators and fast switching devices.

The influence of heat treatment on hole transfer (HT) processes from the CdSe/ZnS and CdSe/CdS/ZnS quantum dots (QDs) to 4,4${}^{\prime }$,4${}^{″}$-Tris(carbazol-9-yl)-triphenylamine (TCTA) in QD/TCTA hybrid films has been researched with time-resolved photoluminescence (PL) spectroscopy. The PL dynamic results demonstrated a heat-treatment-temperature-dependent HT process from the core-shell CdSe QDs to TCTA. The HT rates and efficiencies can be effectively increased due to reduced distance between core-shell CdSe QDs and TCTA after heat treatment. The CdS shell exhibited a more obvious effect on HT from the core-shell CdSe QDs to TCTA than on electron transfer to TiO₂, due to higher barrier for holes to tunnel through CdS shell and larger effective mass of holes in CdS than electrons. These results indicate that heat treatment would be an effective means to further optimize solid-state QD sensitized solar cells and rational design of CdS shell is significant.

The white organic light-emitting devices (WOLED) with the structures of ITO/m-MTDATA (10 nm)/NPB (30 nm)/Rubrene (0.2 nm)/DOPPP (x nm)/TAz (10 nm)/Alq₃ (30 nm)/LiF (0.5 nm)/Al and ITO/NPB (30 nm)/DPAVBi:Rubrene (2 wt.%, 20 nm)/ DOPPP (x nm)/TAZ (10 nm)/Alq₃ (30 nm)/LiF (0.5 nm)/Al (100 nm) have been fabricated by the vacuum thermal evaporation method. The results show that the chroma of the non-doped device is the best and the color coordinates are in the range of white light. The maximum luminance is 12,750 cd/m² and the maximum current efficiency is 8.55 cd/A. The doped device A has the maximum luminance (16,570 cd/m²), when the thickness of blue layer DOPPP is 25 nm, and the doped device B achieves the highest efficiency (10.47 cd/A), when the thickness of DOPPP is 15 nm. All the performances of the doped devices are better than the non-doped one. The results demonstrate that the doped structures can realize the energy transfer and then improve the performance of the device effectively.

Topological phases are important topics in condensed matter physics. Here, we investigate a spin–orbit coupling Bose–Hubbard model in triangular lattice. In the strong coupling limit, we obtained the single particle Green’s function and constructed the phase diagram for ground states. We found two types of nontrivial topological ground phases characterized by spin Chern number and skyrmion number, respectively. The spin Chern numbers characterize the spin Chern insulators. While the skyrmion numbers characterize the skyrmion textures. We show that the phase transitions between different spin Chern insulators take place with gap closing and reopening. While the phase transitions between different skyrmion textures occur without gap closing.

A wideband metasurface filter based on complementary split-ring resonators (CSRR) has been prepared. The frequency and transmission bandwidth of the metasurface filters with different split widths are discussed. After analyzing the mechanism of the metasurface, the proposed metasurface filters are fabricated. The electromagnetic properties of the metasurface are measured by a designed test system. The measured results are in good agreement with the simulated ones, which shows that the metasurface filter has a wideband property. As the split width of the CSRR increases, the frequency of the passband shifts to higher frequency regions and the transmission bandwidth decreases.