NMR/NQR study of Kondo semiconductors CeNiSn and CeRhSb

✍ Scribed by K. Nakamura; Y. Kitaoka; K. Asayama; T. Takabatake; G. Nakamoto; H. Tanaka; H. Fujii

• Publisher: Elsevier Science
• Year: 1995
• Tongue: English
• Weight: 216 KB
• Volume: 206-207
• Category: Article
• ISSN: 0921-4526
• DOI: 10.1016/0921-4526(94)00598-p

✦ Synopsis

The gapped state in Kondo semiconductors CeNiSn and CeRhSb has been investigated by measurements of nuclear-spin laftice relaxation rate, 1/T~ of ll9Sn and 1235b and Knight shift of 1195n and 12~Sb. The T-dependences of T 1 and the shift in both compounds have revealed a novel feature for the gap state at low-T. Especially, the former has established that the energy gap is of a pseudo type with a V-shaped structure, where the band width, D and the pseudogap, A were estimated to be D = 140 and 210 K and A = 14 and 28 K for CeNiSn and CeRhSb, respectively. At very low-T, the TIT= constant behavior has, however, been found in both compounds. The fact that the T~T=constant behavior appears from much higher-T in CeNil.0~Sn and CeNio.97Co0.03Sn suggest that impurities and/or imperfections yield a finite density of states at the Fermi level. Together with the Knight shift result, we highlight that the gapped state in Ce-based compounds belongs to a different class from the activated-type gap state in such as SmB 6 and YbB~2.