Electron shelving of a superconducting artificial atom
Abstract
Interfacing long-lived qubits with propagating photons is a fundamental challenge in quantum technology. Cavity and circuit quantum electrodynamics (cQED) architectures rely on an off-resonant cavity, which blocks the qubit emission and enables a quantum non-demolition (QND) dispersive readout. However, no such buffer mode is necessary for controlling a large class of three-level systems that combine a metastable qubit transition with a bright cycling transition, using the electron shelving effect. Here we demonstrate shelving of a circuit atom, fluxonium, placed inside a microwave waveguide. With no cavity modes in the setup, the qubit coherence time exceeds 50 μs, and the cycling transition’s radiative lifetime is under 100 ns. By detecting a homodyne fluorescence signal from the cycling transition, we implement a QND readout of the qubit and account for readout errors using a minimal optical pumping model. Our result establishes a resource-efficient (cavityless) alternative to cQED for controlling superconducting qubits.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Nov 04, 2021
- Source ID
- 10.1038/s41467-021-26686-x
Entities
People
- Haonan Xiong
- Long B. Nguyen
- Nathanaël Cottet
- Vladimir E Manucharyan
- Yen-hsiang Lin