High-resolution photoemission study of Ce1-xLaxRhAs: a collapse of the energy gap in the Kondo semiconductor
نویسندگان
چکیده
High-resolution resonance-photoemission spectroscopy has been performed on the Ce1-xLaxRhAs (0≤x≤0.05) single crystal to elucidate a collapse of the energy gap in the Kondo semiconductor CeRhAs by La substitution. With increasing x, the spectral intensity of the Ce 4f derived states near the Fermi level decreases and new 4f derived spectral feature appears at a higher binding energy. The Rh 4d-derived states, on the other hand, are not significantly changed by the substitution. New 4f-derived states have incoherent nature, which is responsible for the collapse of the semiconducting state for x>~0.02. © 2005 Elsevier Science. All rights reserved
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