Direct observation of the Ce 4f states in the Kondo semiconductor CeRhAs and related compounds: A high-resolution resonant photoemission study

Article

关键词: ELECTRONIC-STRUCTURE;    CENISN;    BULK;    SPECTROSCOPY;    SURFACE;    MODEL;    EXCITATION;    PSEUDOGAP;    METAL;    GAP;   

DOI  :  10.1103/PhysRevB.66.155202

来源: SCIE

【 摘 要 】

Ce 4f derived states at the Fermi level (E-F) of the isostructural single crystals CeRhAs, CeRhSb, and CePtSn were observed directly by means of high-resolution (DeltaE=18-20 meV), low-temperature (10-12 K) photoemission spectroscopy with a photon energy of hnu=126 eV. The Ce 4f spectrum for the Kondo semiconductor CeRhAs exhibited no peak structure near E-F, and its spectral intensity decreases monotonically above the binding energy similar to90 meV, thereby forming a large gap structure. The spectrum of the semimetal CeRhSb is enhanced above similar to120 meV, but decreases steeply above similar to13 meV, which indicates the existence of a narrow pseudogap at E-F. A clear crystal field excitation at similar to27 meV, and a weak Kondo resonance at E-F, were found in the metal CePtSn.

【 授权许可】

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