Mitchell A K, Landau L A, Fritz L, Sela E
Institute for Theoretical Physics, Utrecht University, Leuvenlaan 4, 3584 CE Utrecht, Netherlands.
Raymond and Beverly Sackler School of Physics and Astronomy, Tel-Aviv University, Tel Aviv 69978, Israel.
Phys Rev Lett. 2016 Apr 15;116(15):157202. doi: 10.1103/PhysRevLett.116.157202. Epub 2016 Apr 13.
We study a charge two-channel Kondo model, demonstrating that recent experiments [Z. Iftikhar et al, Nature (London) 526, 233 (2015)] realize an essentially perfect quantum simulation-not just of its universal physics, but also nonuniversal effects away from the scaling limit. Numerical renormalization group (RG) calculations yield conductance line shapes encoding RG flow to a critical point involving a free Majorana fermion. By mimicking the experimental protocol, the experimental curve is reproduced quantitatively over 9 orders of magnitude, although we show that far greater bandwidth/temperature separation is required to obtain the universal result. Fermi liquid instabilities are also studied: In particular, our exact analytic results for nonlinear conductance provide predictions away from thermal equilibrium, in the regime of existing experiments.
我们研究了一个电荷双通道近藤模型，证明了最近的实验[Z. Iftikhar等人，《自然》（伦敦）526, 233 (2015)]实现了一个基本完美的量子模拟——不仅是对其普适物理，还包括远离标度极限的非普适效应。数值重整化群（RG）计算得出的电导线形编码了向涉及自由马约拉纳费米子的临界点的RG流。通过模仿实验方案，尽管我们表明要获得普适结果需要大得多的带宽/温度分离，但实验曲线在9个数量级上被定量重现。我们还研究了费米液体不稳定性：特别是，我们关于非线性电导的精确解析结果给出了在现有实验范围内远离热平衡的预测。
