KONDO-LATTICE METALS AND SEMICONDUCTORS WITH COMPENSATED MAGNETIC MOMENTS : A BRIEF OVERVIEW
KONDO-LATTICE METALS AND SEMICONDUCTORS WITH COMPENSATED MAGNETIC MOMENTS : A BRIEF OVERVIEW
复制标题
具有补偿磁矩的近藤晶格金属和半导体：简要概述
DOI：
10.12693/aphyspola.96.677
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发表时间：
1999
影响因子：
0.7
通讯作者：
R. Doradziński
中科院分区：
文献类型：
--
作者：
J. Spałek;R. Doradziński
在过去的二十年里，重费米子系统一直是人们研究的热点。人们的兴趣始于发现[1]，即具有质量为m* 103 m0的重准粒子的金属系统CeCu 2Si 2，其中m0是自由电子质量，在温度TS 1 K以下是超导体。另外两项研究结果也激发了人们对这些系统的兴趣。首先[2]，其中一些系统，如Ce 3Bi 4Pt 3或YbB 12在温度T = 0 K时是绝缘的，但随着温度的升高成为重费米子金属。它们被称为近藤绝缘体。第二，在T < 1 K时，几种金属体系表现出强烈的费米液体行为偏离。也就是说，我们遇到了线性比热系数y（T）<$C（T）/Tln（T0/T）的行为，磁化率x（T）~ x 0（1 - αvT）的依赖关系，以及电阻率行为pp 0-lAl '，其中T0，x 0，α，p0和A'是常数。这些温度依赖性通常被称为非费米液体行为（严格地说，它们应该被称为费米液体的非朗道行为）。人们应该从一开始就认识到这些结果的根本意义。首先，电子几乎和核子一样重，应该被认为非常接近莫特定域点（在该点，处于定域或原子态的电子获得无限大的有效质量，以便在整个系统中进行平移运动）。它们几乎是局域化的（即在费米能级具有大的态密度）这一事实意味着它们具有良好定义的磁性
The heavy-fermion systems have been studied intensively during the two last decades. The interest started with the discovery [1] that the metallic system CeCu2Si2 with the heavy quasiparticles of mass m* 103 m0, where m0 is the free-electron mass, are superconductors below the temperature TS 1 K. The interest in those systems was also stimulated by two further findings. First [2], some of those systems such as Ce3 Bi4 Pt3 or YbB 12 are insulating at temperature T = 0 K, but become heavy-fermion metals with increasing temperature. They are called the Kondo insulators. Second [3], several metallic systems exhibit strong deviations from the Fermi-liquid behavior at T < 1 K. Namely, one encounters the behavior of the linear-specific-heat coefficient y(T) ≡ C(T)/T ln(T0/T), the dependence for the magnetic susceptibility x(T) ~ x0(1 — αvT), and the resistivity behavior p p0 -lAl', where T0, x0, α, po, and A' are constants. These temperature dependences are commonly termed a non-Fermi liquid behavior (strictly, they should be called a non-Landau behavior of fermionic liquids). One should recognize at the outset a fundamental significance of those results. First, the electrons, almost as heavy as the nucleons, should be regarded as being very close to the Mott localization point (at which the electrons in the localized or atomic states acquire infinite effective mass for translational motion throughout the system). The fact that they are almost localized (i.e. have large density of states at the Fermi level) means that they have well defined magnetic