CeNS Colloquium

Prof. Gerhard Kirchmair, Universität Innsbruck

The recent development of a 3D architecture for superconducting circuits has dramatically increased the coherence time of qubits and cavities. With our setup we can access the strong dispersive coupling regime which allows us to detect the presence and absence of single microwave photons in our cavity. With the tools and techniques we have developed we can manipulate the quantum state of the cavity by applying operations conditioned on the state of a superconducting qubit. This allows us to realize a protocol that deterministically maps a qubit state to a superposition of coherent states in a cavity. We extend this method to create multi-component Schrödinger cat states. These states include the four-component compass state that can be used to realize a quantum memory protected against spontaneous emission.

In this talk I will give an introduction to circuit quantum electrodynamics and the 3D architecture. Then I will present the tools used to do quantum optics experiments and create Schrödinger cat states. In the last part of my talk I want to present a project we have recently started in our group, on how to realize an analog quantum simulator of 2D spin lattices using superconducting qubits.