Superconducting circuits for quantum information technology

The 1999 demonstration of quantum coherence in a superconducting circuit has inspired remarkable progress towards all-electronic quantum processors based on Josephson-junction circuits. We can now initialize, coherently control and measure quantum circuits meeting most of DiVincenzo’s feasibility criteria with fidelities approaching modern fault-tolerance thresholds. In this talk, I will highlight important recent developments in the field, including the preparation and detection of multi-qubit entanglement violating Bell and Mermin-type inequalities, and the realization of rudimentary quantum algorithms and error correction. I will also present first efforts to shift from open-to closed-loop control of these circuits, as will be necessary for surface-code error correction and for distribution of quantum states and entanglement across future quantum networks.