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arXiv 1609.06165cond-mat.mes-hallcond-mat.str-el
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究竟在哪个磁场上,近藤共振开始分裂?Anderson模型低能性质的费米液体描述

At which magnetic field, exactly, does the Kondo resonance begin to split? A Fermi liquid description of the low-energy properties of the Anderson model

Michele Filippone, Catalin Pascu Moca, Andreas Weichselbaum, Jan von Delft, Christophe Mora

摘要:

这篇论文是Phys. Rev. B 95,165404(2017)的更正版本,我们已经撤回了它,因为它包含了一个微不足道但致命的符号错误,导致了不正确的结论。- 我们推广了最近发展起来的非对称单杂质Anderson模型的费米液体理论[C. Mora $et al.$,Phys.Rev.B,92,075120(2015)]的方法应用于任意局部磁场的情况。为了描述系统的低准粒子激发的裸哈密顿量的模型参数的任意值,我们构建了一个有效的低能FL哈密顿量的FL参数表示的本地水平的自旋相关的基态占领和他们的衍生物相对于能级能量和本地磁场。这些量可以从Anderson模型的Bethe Anglesia解以极好的精度计算。将此有效模型应用于非平衡态量子点,得到了描述其首项$\sim\varepsilon^2$的谱函数$c_A$的曲率,以及描述非线性微分电导中首项$\sim V^2$和$\sim T^2$的输运系数$c_V$和$c_T$的精确结果. $c_A$或$c_V$中的符号变化分别指示谱函数或非线性电导中从局部最大值到局部最小值的变化,如当增加的磁场导致近藤共振分裂成两个子峰时预期发生的。我们发现,$c_A$,$c_T$和$c_V$分别改变符号的字段$B_A$,$B_T$和$B_V$都是$T_K$阶,正如预期的那样,$B_A = B_T = B_V = 0.75073\,T_K$在Kondo极限中。

英文摘要:

This paper is a corrected version of Phys. Rev. B 95, 165404 (2017), which we have retracted because it contained a trivial but fatal sign error that lead to incorrect conclusions. --- We extend a recently-eveloped Fermi-liquid (FL) theory for the asymmetric single-impurity Anderson model [C. Mora $et al.$, Phys. Rev. B, 92, 075120 (2015)] to the case of an arbitrary local magnetic field. To describe the system's low-lying quasiparticle excitations for arbitrary values of the bare Hamiltonian's model parameters, we construct an effective low-energy FL Hamiltonian whose FL parameters are expressed in terms of the local level's spin-dependent ground-state occupations and their derivatives with respect to level energy and local magnetic field. These quantities are calculable with excellent accuracy from the Bethe Ansatz solution of the Anderson model. Applying this effective model to a quantum dot in a nonequilibrium setting, we obtain exact results for the curvature of the spectral function, $c_A$, describing its leading $\sim\varepsilon^2$ term, and the transport coefficients $c_V$ and $c_T$, describing the leading $\sim V^2$ and $\sim T^2$ terms in the nonlinear differential conductance. A sign change in $c_A$ or $c_V$ is indicative of a change from a local maximum to a local minimum in the spectral function or nonlinear conductance, respectively, as is expected to occur when an increasing magnetic field causes the Kondo resonance to split into two subpeaks. We find that the fields $B_A$, $B_T$ and $B_V$ at which $c_A$, $c_T$ and $c_V$ change sign, respectively, are all of order $T_K$, as expected, with $B_A = B_T = B_V = 0.75073\,T_K$ in the Kondo limit.

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