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Register a new userSingle crystal growth and physical property characterizations of mixed valent compound YbFe$_2$Al$_{10}$
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We report single crystal growth and physical properties characterization of YbFe$_2$Al$_{10}$ compounds. The measurements of resistivity, magnetic susceptibility, and specific heat show different behaviors from previous studies on polycrystal samples. A mixed valent characteristic with moderate mass enhancement is indicated. In particular, the optical spectroscopy measurement reveals formation of multiple hybridization energy gaps which become progressively pronounced at low temperature. The multiple hybridization energy gaps are likely caused by the hybridizations between the flat band from Yb 4$f$ electrons and different bands of conduction electrons.
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We have grown the new uranium compound URhIn$_5$ with the tetragonal HoCoGa$_5$-type by the In self flux method. In contrast to the nonmagnetic ground state of the isoelectronic analogue URhGa$_5$, URhIn$_5$ is an antiferromagnet with antiferromagnetic transition temperature $T_{rm N}$ = 98 K. The moderately large electronic specific heat coefficient $gamma$ = 50 mJ/K$^2$mol demonstrates the contribution of 5$f$ electrons to the conduction band. On the other hand, magnetic susceptibility in the paramagnetic state roughly follows a Curie-Weiss law with a paramagnetic effective moment corresponding to a localized uranium ion. The crossover from localized to itinerant character at low temperature may occur around the characteristic temperature 150 K where the magnetic susceptibility and electrical resistivity show a marked anomaly.
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Single crystal of Cu0.03TaS2 with low copper intercalated content was successfully grown via chemical iodine-vapor transport. The structural characterization results show that the copper intercalated 2H-Cu0.03TaS2 single crystal has the same structure of the CdI2-type structure as the parent 2H-TaS2 crystal. Electrical resistivity and magnetization measurements reveal that 2H-Cu0.03TaS2 becomes a superconductor below 4.2 K. Besides, electrical resistivity and Hall effects results show that a charge density wave transition occurs at TCDW = 50 K.
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