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تسجيل مستخدم جديدFar-infrared probe of superconductivity in SmO$_{1-x}$F$_{x}$FeAs}
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We report far-infrared reflectance measurements on polycrystalline superconducting samples of SmO$_{1-x}$F$_{x}$FeAs ($x$ = 0.12, 0.15 and 0.2). We clearly observe superconductivity induced changes of reflectivity in a broad range of energies, which resembles earlier optical measurements on high $T_{c}$ cuprates. The superconducting-to-normal reflectivity ratio $R_{s}/R_{n}$ grows for the photon energies below 18 meV and shows a complicated structure due to the presence of a strong infrared-active phonon at about 10 meV.
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We investigated the temperature dependence of the density-of-states in the iron-based superconductor SmO_1-xF_xFeAs (x=0, 0.12, 0.15, 0.2) with high resolution angle-integrated photoemission spectroscopy. The density-of-states suppression is observed
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The specific heat $C(T)$ of new iron-based high-$T_c$ superconductor SmO$_{1-x}$F$_x$FeAs ($0 leq x leq 0.2$) was systematically studied. For undoped $x$ = 0 sample, a specific heat jump was observed at 130 K. This is attributed to the structural or
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