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Based on the high quality FeSe 1− x S x (0 ≤ x ≤ 1) single crystals synthesized via a hydrothermal method, we carried out systematic measurement of the normal state magnetoresistance and Hall effect. Through the maximum entropy mobility spectrum analysis (MEMSA), we investigate the evolution of mobility spectrum, which reflects the multi-band structures for different doping content x and temperature T. The relationships between T c and carrier properties calculated by MEMSA, as well as bond angles and anion height calculated by first-principle method are investigated. Nonlinear to linear transition of Hall resistivity(ρ xy (B)) is mainly attributed to the decreasing mobilities and merging of mobility peaks with the reductive x or increasing T. The relationship between T c and carrier density n show weak interaction for the orthogonal phases when x ≤ 0.2, but nearly positive correlation for the tetragonal phases when x > 0.2. Bond angle as well as the Se/S anion height change almost linearly with x within the tetragonal phases, and the V-shaped relationships with T c indicate that structural factors play a key role in the regulation of superconductivity. Our researches are helpful for understanding the multi-band and complex phase diagram of iron-based superconductors. • We systematically measured magnetoresistance and Hall resistivity of FeSe 1−x S x (0 ≤ x ≤ 1) single crystals. • Nonlinear to linear transition of Hall resistivity is mainly due to decreasing mobilities and merging of mobility peaks. • The bond angle and Se/S anion height both show V-shaped relationships with T c. • Structural factors play a key role in the regulation of superconductivity in iron-based superconductors. [ABSTRACT FROM AUTHOR]

We reported a detailed study of Fe 1+ y Te 0.6 Se 0.4 single crystals annealed in the atmosphere of chalcogens (O 2 , S, Se, Te). After annealing with appropriate amount of chalcogens, Fe 1+ y Te 0.6 Se 0.4 single crystals show T c higher than 14 K with a sharp transition width ∼1 K. Critical current density J c for the annealed crystals reach a very high value ∼2–4 × 10 5 A/cm 2 under zero field, and is also robust under applied field at low temperatures. Magneto-optical imaging reveal that the J c is homogeneously distributed in the annealed crystals and isotropic in the ab -plane. Our results show that annealing in the atmosphere of chalcogens can successfully induce bulk superconductivity in Fe 1+ y Te 0.6 Se 0.4 . [ABSTRACT FROM AUTHOR]

Abstract: The effect of orientation on the creep properties of DD6 single crystal superalloy is investigated. The results show that anisotropic creep behaviors of DD6 alloy within 20° of the [001] direction are observed at 760°C and 785MPa. The [001] direction and the [001]–[011] boundary exhibit lower primary creep strain and longer creep rupture lives than the [001]–[111] boundary. In addition, the major creep deformation mechanism of DD6 single crystal superalloy at 760°C and 785MPa is a〈112〉 dislocation ribbon passing through both γ and γ′ phases. The interaction between 〈112〉{111} systems is the principle hardening mechanism for the transition from primary creep to secondary creep, the interaction leads to the anisotropy of primary creep and creep rupture lives for the [001] direction, the [001]–[011] boundary and the [001]–[011] boundary. [Copyright &y& Elsevier]