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The CP violation in the D system is predicted to be an unobserved level in the Standard Model. In this paper, we describe the method of searching for CP violation decay processes with the coherently produced D0 D0 mesons from the ps(3770) decay. The CP violation decay processes can be searched for at the BES-III experiment. The experimental sensitivity for searching for the CP violation can reach about a 10[?]4 level with a ps(3770) data sample of about 20 fb[?]1. [ABSTRACT FROM AUTHOR]

We have performed magnetization measurements and electron spin resonance (ESR) on polycrystalline manganites of Nd0.5Sr0.5-xBaxMnO3 (x = 0.1). Phase separation and phase transitions are observed from the susceptibility and the ESR spectra data. Between 260K ([?] TC) and 185K ([?] TN), the system coexists of the paramagnetic phase and the ferromagnetic (FM) phase. Between 185K and 140K, the system coexists of the FM phase and the antiferromagnetic (AFM) phase. These results indicate that the system has a very complex magnetic state due to the origin of the instability stemming from manganite Nd0.5Sr0.4Ba0.1MnO3 by partially substituting the larger Ba2+ ions for the smaller Sr2+ ions. [ABSTRACT FROM AUTHOR]

The band structure, density of states, optical properties, carrier mobility, and loss function of graphene, black phosphorus (BP), and molybdenum disulfide (MoS2) were investigated by the first-principles method with the generalized-gradient approximation. The graphene was a zero-band-gap semiconductor. The band gaps of BP and MoS2 were strongly dependent on the number of layers. The relationships between layers and band gap were built to predict the band gap of few-layer BP and MoS2. The absorption showed an explicit anisotropy for light polarized in (1 0 0) and (0 0 1) directions of graphene, BP, and MoS2. This behavior may be readily detected in spectroscopic measurements and exploited for optoelectronic applications. Moreover, graphene (, BP (, and MoS2 ( have high carrier mobility. These results show that graphene, BP, and MoS2 are promising candidates for future electronic applications. [ABSTRACT FROM AUTHOR]

Graphene-based resistive random access memory (GRRAM) has grasped researchers’ attention due to its merits compared with ordinary RRAM. In this paper, we briefly review different types of GRRAMs. These GRRAMs can be divided into two categories: graphene RRAM and graphene oxide (GO)/reduced graphene oxide (rGO) RRAM. Using graphene as the electrode, GRRAM can own many good characteristics, such as low power consumption, higher density, transparency, SET voltage modulation, high uniformity, and so on. Graphene flakes sandwiched between two dielectric layers can lower the SET voltage and achieve multilevel switching. Moreover, the GRRAM with rGO and GO as the dielectric or electrode can be simply fabricated. Flexible and high performance RRAM and GO film can be modified by adding other materials layer or making a composite with polymer, nanoparticle, and 2D materials to further improve the performance. Above all, GRRAM shows huge potential to become the next generation memory. [ABSTRACT FROM AUTHOR]

In this paper, we study the quantum properties of a bilayer graphene with (asymmetry) line defects. The localized states are found around the line defects. Thus, the line defects on one certain layer of the bilayer graphene can lead to an electric transport channel. By adding a bias potential along the direction of the line defects, we calculate the electric conductivity of bilayer graphene with line defects using the Landauer–Büttiker theory, and show that the channel affects the electric conductivity remarkably by comparing the results with those in a perfect bilayer graphene. This one-dimensional line electric channel has the potential to be applied in nanotechnology engineering. [ABSTRACT FROM AUTHOR]

Low metal–graphene contact resistance is important in making high-performance graphene devices. In this work, we demonstrate a lower specific contact resistivity of Au0.88Ge0.12/Ni/Au–graphene contact compared with Ti/Au and Ti/Pt/Au contacts. The rapid thermal annealing process was optimized to improve AuGe/Ni/Au contact resistance. Results reveal that both pre- and post-annealing processes are effective for reducing the contact resistance. The specific contact resistivity decreases from 2.5 × 10−4 to 7.8 × 10−5 Ω·cm2 by pre-annealing at 300 °C for one hour, and continues to decrease to 9.5 × 10−7 Ω·cm2 after post-annealing at 490 °C for 60 seconds. These approaches provide reliable means of lowering contact resistance. [ABSTRACT FROM AUTHOR]

Asymmetry in dislocation density and strain relaxation has a significant impact on device performance since it leads to anisotropic electron transport in metamorphic materials. So it is preferred to obtain metamorphic materials with symmetric properties. In this paper, we grew metamorphic In0.27Ga0.73As epilayers with symmetric low threading dislocation density and symmetric strain relaxation in two 〈110〉 directions using InAlGaAs buffer layers on 7° misoriented GaAs (001) substrates. To understand the control mechanism of symmetric properties of In0.27Ga0.73As layers by the substrate miscut angles, In0.27Ga0.73As grown on 2° and 15° misoriented substrates were also characterized as reference by atomic force microscopy, transmission electron microscopy, and high resolution triple axis x-ray diffraction. The phase separation and interaction of 60° misfit dislocations were found to be the reasons for asymmetry properties of In0.27Ga0.73As grown on 2° and 15° substrates, respectively. Photoluminescence results proved that the In0.27Ga0.73As with symmetric properties has better optical properties than the In0.27Ga0.73As with asymmetric properties at room temperature. These results imply that high quality metamorphic In0.27Ga0.73As can be achieved with controllable isotropic electron transport property. [ABSTRACT FROM AUTHOR]