论文标题
热力学和筛查Ising-Kondo模型
Thermodynamics and screening in the Ising-Kondo model
论文作者
论文摘要
我们介绍并研究了对称性单障碍围绕模型的简化。在Ising-Kondo模型中，宿主电子在动态保守的旋转方向的原点上散布了单个磁杂质。这将问题降低为无旋转费米的潜在散射，这些散射可以使用运动方程式技术来精确求解。 Ising-Kondo模型为静态筛选提供了一个示例。在低温下，有限磁场的热力学类似于降低的外部场中的自旋1/2。另外，可以用抗磁性筛选的有效旋转来解释居里定律。自旋相关性在基态下以代数为零，并显示相应的弗里德尔振荡。与对称的围绕模型相反，杂质旋转未完全筛选，即筛选云包含的含量小于Spin-1/2电子。在有限的温度和弱相互作用下，自旋相关性衰减呈指数为零，相关长度$ξ（t）= 1/（2πt）$。
We introduce and study a simplification of the symmetric single-impurity Kondo model. In the Ising-Kondo model, host electrons scatter off a single magnetic impurity at the origin whose spin orientation is dynamically conserved. This reduces the problem to potential scattering of spinless fermions that can be solved exactly using the equation-of-motion technique. The Ising-Kondo model provides an example for static screening. At low temperatures, the thermodynamics at finite magnetic fields resembles that of a free spin-1/2 in a reduced external field. Alternatively, the Curie law can be interpreted in terms of an antiferromagnetically screened effective spin. The spin correlations decay algebraically to zero in the ground state and display commensurate Friedel oscillations. In contrast to the symmetric Kondo model, the impurity spin is not completely screened, i.e., the screening cloud contains less than a spin-1/2 electron. At finite temperatures and weak interactions, the spin correlations decay to zero exponentially with correlation length $ξ(T)=1/(2πT)$.
