High-resolution temperature-dependent photoemission study of Kondo semimetal CeNiSn

The temperature dependence of the electronic slates of Kondo semimetal CeNiSn has been studied by high-resolution photoemission spectroscopy. The results have been compared with those of LaNiSn. The temperature-dependent spectral weight reduction of CeNiSn is observed below 30 K at binding energies between similar to 20 meV and E-F, and is similar to that of the Kondo insulator Ce3Bi4Pt3. This behavior is not observed For LaNiSn. The spectral intensity of Ce 4f derived state near the Fermi level (E-F) is enhanced at temperatures above a characteristic temperature, but the spectral intensity at E-F is reduced at 7 K. (C) 2000 Elsevier Science B.V. All rights reserved.