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Specific heat and transport properties are measured on good single crystals of SmB6. The specific heat experiment indicates that there is a gap of near 100 K in the 4f system leaving a very small T linear term. Conductivity experiment indicates that the usual hopping type conductivity changes to a constant value without activation which is, however, three orders of magnitude smaller than the so far believed minimum metallic conductivity. The usual Anderson localization proposed before by us is clearly not applicable. Here, we propose a model of a new type of the Wigner lattice formation. Various anomalous properties mentioned above are explained within this model

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We have performed a temperature dependent angle-resolved photoemission spectroscopy (ARPES) study of the tri-layer high-Tc cuprate superconductor (HTSC) Bi2Sr2Ca2Cu3O 10+δ (Bi2223), and have shown that the "effective"superconducting (SC) gap ∆sc defined at the end point of the Fermi arc and the Tc (= 110 K) approximately satisfies the weak-coupling BCS-relationship 2∆sc = 4.3kBTc. Combining this result with previous ARPES results on single-and double-layer cuprates, we show that the relationship between 2∆sc = 4.3kBTc holds for various HTSCs. Furthermore, at T ∼ Tc, the quasi-patricle width at the end point of the Fermi arc is found to coincide with ∆sc, consistent with the context of Planckian dissipation.

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