Observation of quantum jumps in a superconducting artificial atom

Understand

A continuously monitored quantum system prepared in an excited state will decay to its ground state with an abrupt jump.

• The jump occurs stochastically on a characteristic time scale T1, the lifetime of the excited state.
• These quantum jumps, originally envisioned by Bohr, have been observed in trapped atoms and ions, single molecules, photons, and single electrons in cyclotrons.
• Here we report the first observation of quantum jumps in a macroscopic quantum system, in our case a superconducting "artificial atom" or quantum bit (qubit) coupled to a superconducting microwave cavity.