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High resolution angle-resolved photoemission measurements have been carried out to study the superconducting gap in the (Ba0.6K0.4)Fe2As2 superconductor with Te = 35 K. Two hole-like Fermi surface sheets around the I' point exhibit different superconducting gaps. The inner Fermi surface sheet shows larger (10 [?] 12 meV) and slightly momentum-dependent gap while the outer one has smaller (7 [?] 8meV) and nearly isotropic gap. The lack of gap node in both Fermi surface sheets favours s-wave superconducting gap symmetry. Superconducting gap opening is also observed at the M(p, p) point. The two Fermi surface spots near the M point are gapped below Te but the gap persists above Te. The rich and detailed superconducting gap information will provide key insights and constraints in understanding pairing mechanism in the iron-based superconductors. [ABSTRACT FROM AUTHOR]

High resolution angle-resolved photoemission measurements are carried out to systematically investigate the effect of cleaving temperature on the electronic structures and Fermi surfaces of Sr2RuO4. Unlike previous reports, which found that a high cleaving temperature can suppress the surface Fermi surface, we find that the surface Fermi surface remains obvious and strong in Sr2RuO4 cleaved at high temperature, even at room temperature. This indicates that cleaving temperature is not a key effective factor in suppressing surface bands. On the other hand, the bulk bands can be enhanced in an aged surface of Sr2RuO4 that has been cleaved and held for a long time. We have also carried out laser ARPES measurements on Sr2RuO4 by using a vacuum ultra-violet laser (photon energy at 6.994 eV) and found an obvious enhancement of bulk bands even for samples cleaved at low temperature. This information is important for realizing an effective approach to manipulating and detecting the surface and bulk electronic structure of Sr2RuO4. In particular, the enhancement of bulk sensitivity, along with the super-high instrumental resolution of VUV laser ARPES, will be advantageous in investigating fine electronic structure and superconducting properties of Sr2RuO4 in the future. [ABSTRACT FROM AUTHOR]