Figure 1

(a) A chaotic cavity with two attached waveguides and a classical trajectory contributing to conductance and shot noise. (b) The quantum graph used to model this situation. The transversal modes of the waveguides correspond to the infinite leads attached to the graph (bold lines), while the internal system is represented by many finite bonds.Reuse & Permissions

Figure 2

(a) Shown schematically are four classical trajectories $p,q,r,s$ connecting two incoming modes $m_1,n_1$ to two outgoing modes $m_2,n_2$ such that the diagram contributes to the semiclassical approximation of Eq. (2). A contribution to Eq. (6) results only if the trajectories are correlated such that the action difference between $p,r$ (solid lines) and $q,s$ (dashed lines) remains small for varying energy. (b),(c) The simplest configurations where this is the case: Two trajectories are pairwise equal (diagonal approximation). (d) The configuration which completely accounts for the universal shot noise in leading order.Reuse & Permissions