911±¬ÁÏÍø

Protecting and interconnecting superconducting qubits

Johannes Fink (Institute of Science and Technology Austria (ISTA))

Abstract: The talk covers two frontiers: 

i) Protecting superconducting qubit states at the hardware level: Fluxon states localized in ultra-heavy fluxonium circuits (IST qubits) have remarkably reached T₁ times exceeding three hours close to the half-flux point. This exponential protection with E_j holds the promise of a strongly noise-biased qubit platform. Yet, coherent control is challenging due to the suppressed matrix elements. In this talk, we present a proposal and some experimental progress toward achieving universal control of such circuits that relies only on baseband flux pulses. 

ii) Optical interconnects between superconducting qubit modules: After reviewing aspects of electro-optic conversion and qubit readout I'll present the upconversion and subsequent detection of non-classical single microwave photon Fock states. This represents a paradigm shift toward loss resilient entanglement generation schemes for superconducting qubit interconnects based on heralding and teleportation. Specifically, I will outline our team's progress toward entangling superconducting qubits with time-bin encoded telecom wavelength single photon states propagating at room temperature.