Real-Time Diagrammatic Theory of Electron Waiting Time Distributions: Interaction Effects and Higher-Order Tunneling Processes
We develop a real-time diagrammatic theory of electron waiting time distributions for quantum transport in strongly interacting nanostructures. While existing methods address either weakly coupled systems with strong Coulomb interactions or coherent transport in mesoscopic conductors without interactions, our approach makes it possible to treat the interesting intermediate regime where both interaction effects and higher-order tunneling processes are important. As an illustration of experimental relevance, we consider a quantum dot coupled to electronic reservoirs and find that the distribution of waiting times between transferred electrons is drastically affected by virtual charge fluctuations and higher-order tunneling processes such as cotunneling that lead to non-Markovian dynamics on the quantum dot, and which can now be accounted for by our theoretical framework.