Low-Energy Excitation in Kondo Semiconductors CeNiSn and CeRhSb.
Low-Energy Excitation in Kondo Semiconductors CeNiSn and CeRhSb.
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近藤半导体 CeNiSn 和 CeRhSb 的低能量激发。
DOI：
10.1143/jpsj.63.433
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发表时间：
1994
影响因子：
1.7
通讯作者：
H. Fujii
中科院分区：
文献类型：
--
作者：
K. Nakamura;Y. Kitaoka;K. Asayama;T. Takabatake;Hiroaki Tanaka;H. Fujii
通过测量近藤半导体CeNiSn和CeRhSb的119 Sn和123 Sb核自旋-晶格弛豫速率1/T1，研究了近藤半导体的低能激发。从这两种化合物的1/T1的类T3温度依赖性，已经直观地得出结论，具有V形结构的赝能隙形成的有效态密度的重准粒子。CeRhSb的禁带宽度为D =210 K，赝能隙为Δ=28 K，分别比CeNiSn的禁带宽度（D =140 K）和赝能隙（Δ=14 K）大近两倍。CeNiSn和CeRhSb分别低于0.4K和0.8K时，T1 T = const .在这两种化合物中通常观察到这种行为，表明在费米能级存在残余态密度。样品中的杂质和/或缺陷在非常低的温度下容易掩盖能隙的本征V形结构。
Low-energy excitation in Kondo semiconductors CeNiSn and CeRhSb, has been investigated by the measurement of 119 Sn and 123 Sb nuclear spin-lattice relaxation rate, 1/ T 1 . From a T 3 -like temperature dependence of 1/ T 1 for both compounds, it has been intuitively concluded that the pseudo energy gap with the V - shaped structure is formed in the effective density of states for heavy quasi-particles. The band width of D =210 K and the pseudo energy gap of Δ=28 K in CeRhSb are almost two times larger than those of CeNiSn ( D =140 K and Δ=14 K), respectively. Below 0.4 K and 0.8 K for CeNiSn and CeRhSb, respectively, the T 1 T = const . behavior has been commonly observed in the two compounds, indicative of the presence of a residual density of states at the Fermi level. Impurities and/or imperfection in the samples easily mask the intrinsic V - shaped structure of the energy gap at very low temperatures.