Probing dynamics of Majorana fermions in quantum impurity systems
Résumé
We investigate the admittance of a metallic quantum RC circuit with a spinful single-channel lead or equally with two conducting spin-polarized channels, as an ideal system to probe the dynamics of Majorana fermions. We address how the two-channel Kondo physics and its emergent Majoranas arise and we determine the universal crossover function describing the Fermi-liquid to non-Fermi liquid region. Remarkably, the same universal form emerges both at weak transmission and large transmission. We find that the charge relaxation resistance strongly increases in the non-Fermi liquid realm. Our findings can be measured using current technology assuming a large cavity.