Deterministic creation of Schrodinger cat states in a superconducting waveguide cavity

Off-resonant coupling of a superconducting transmon qubit to a three-dimensional waveguide cavity provides a dispersive qubit/cavity interaction much stronger than any decay rates in the system. Using a two-cavity/single-qubit architecture, we utilize this interaction to deterministically map a qubit state to a superposition of coherent states in a cavity (up to a 40 photon separation). By measuring photon-number parity, we perform Wigner tomography that shows the characteristic interference inherent in quantum superpositions, thus confirming the non-classical properties of the cavity state. Furthermore, we extend this method[1] to create multi-component Schrodinger cat states including the four-component compass state. [1] Z. Leghtas et al. Deterministic protocol for mapping a qubit to coherent state superpositions in a cavity. arXiv.org quant-ph 1208.1603 (2012).