Deterministically encoding quantum information using 100-photon Schrödinger cat states

Coherently Controlling Large Cats The control and manipulation of quantum information based on superconducting circuits is an attractive route because of the possibility of scale-up. Vlastakis et al. (p. 607 , published online 26 September; see the Perspective by Leek ) were able to generate and control quantum entanglement between a superconducting qubit and hundreds of photons stored in a cavity resonator by using deterministic methods for on-demand generation of large Schrödinger cat states in a microwave cavity with arbitrary size and phase. The ability to map the state of a qubit to large Schrödinger cat states should provide a robust quantum resource in future quantum-based technologies.