论文标题
Wiedemann-Franz散布理论的法律重新审视
Wiedemann-Franz law in scattering theory revisited
论文作者
论文摘要
在量子运输实验中广泛讨论了对Wiedemann-Franz（WF）定律的侵犯，这是与费米 - 液体行为偏差的指示。 WF法律的常规形式仅与Fermi-Level的传输功能有关，但是在许多实际情况下，这种功能在许多实际情况下都消失了。我们将WF法律重新分配给具有零能量传输的非相互作用量子系统，并报告通用数量$ 21/5 $作为Lorenz比率$ \ MATHSCR {R} $的上限，以弱能量依赖性散射理论。我们为观察$ \ Mathscr {r} = 21/5 $的观察提供了不同的实验实现，即使用石墨烯，多级量子点和双量子点的传输设置。报道的通用洛伦兹比率铺平了一种有效的方法，可以实验获取有关系统中相关量子干扰的信息。我们的工作还提供了足够的证据，这些证据得出结论，违反WF法律并不一定暗示着基本运输过程的非弗米液体性质；同样，观察到的WF法律的验证不能结论费米 - 液体运输特性。
The violation of Wiedemann-Franz (WF) law has been widely discussed in quantum transport experiments as an indication of deviation from Fermi-liquid behavior. The conventional form of WF law is only concerned with the transmission function at Fermi-level which, however, vanishes in many practical situations. We reinvestigate the WF law in noninteracting quantum systems with vanishing zero energy transmission and report a universal number $21/5$ as an upper bound of Lorenz ratio $\mathscr{R}$ in weakly energy-dependent scattering theory. We provide different experimental realizations for the observation of $\mathscr{R}=21/5$ namely the transport setups with graphene, the multi-level quantum dot and double quantum dot. The reported universal Lorenz ratio paves an efficient way of experimentally obtaining the information about the associated quantum interferences in the system. Our work also provides enough evidence which concludes that the violation of WF law does not necessarily imply the non-Fermi-liquid nature of underlying transport processes; equally, the Fermi-liquid transport characteristics cannot be concluded by an observed validation of WF law.
