Physics & Astronomy Quantum Nano Seminar - Anja Metelmann, Princeton University - N.A. - (Hanover, NH)

Abstract: As superconductor quantum technologies are moving towards large-scale integrated circuits, a robust and flexible approach to routing photons at the quantum level becomes a critical problem. Active circuits, which contain parametrically driven elements selectively embedded in the circuit offer a viable solution. In this talk, we discuss a general strategy for routing nonreciprocally quantum signals between 2 sites of a given lattice of oscillators, implementable with existing superconducting circuit components. Our approach makes use of a dual lattice of overdamped oscillators linking the nodes of the main lattice. Solutions for spatially selective driving of the lattice elements can be found, which optimally balance coherent and dissipative hopping of microwave photons to nonreciprocally route signals between 2 given nodes. In certain lattices these optimal solutions are obtained at the exceptional point of the dynamical matrix of the network. We also