Kondo temperature for a quantum dot in an Aharonov-Bohm ring

We study the Kondo temperature of a quantum dot embedded into one arm of an Aharonov-Bohm interferometer. The topology of a disordered or chaotic Aharonov-Bohm ring leads to a stochastic term in the scaling equation and in the renormalization procedure. As a result, the Kondo temperature displays significant fluctuations as a function of magnetic flux.

Figure 1

Distribution of Kondo temperatures $T_K$, for $\cos \varphi =0.5$ (narrow distribution) and $\cos \varphi =1$ (wide distribution), both for $⟨T_K⟩∕\Delta =5$. Each histogram contains ${10}^4$ scaling trajectories. Inset: typical scaling trajectories for $\cos \varphi =1$.