Spectroscopy of hot electron pair emission from a driven quantum dot

On-demand emission of individual electrons for the implementation of flying qubits and quantum electron-optics experiments requires precise knowledge and tunability of emission times and energies. Crucially, for confined electron sources such as driven quantum dots, the effect of local Coulomb interaction on these emission properties needs to be understood, in particular if multiple particles are emitted close in time or near simultaneously. This paper theoretically analyzes electron pair emission from an ac driven quantum dot, detailing the competing effects of the electron-electron interaction, the time-dependent potential forming the quantum dot, and of the quantum-state properties, such as degeneracy, on the emission times and energies. We complement a numerical analysis of the coherent Schrödinger evolution of two particles in a driven potential with a master-equation description for strongly interacting electrons tunneling stochastically into a weakly coupled conductor. This captures a broad range of different influences on the emitted particles and thereby guides the development of single-electron sources with higher control over two-particle emission properties.