Scientists Catch Sound Making a Quantum Jump With a Microscopic Tuning Fork

Scientists Catch Sound Making a Quantum Jump With a Microscopic Tuning Fork

Learn how physicists overcame obstacles to watch phonons quantum jump in real-time.

Stanford physicists observe a quantum jump of sound for the first time

Stanford physicists directly watched a single phonon vanish from a mechanical resonator, revealing quantum jumps of sound in real time.

For more than a century, quantum theory has said a vibrating object should lose energy in discrete packets even though its motion appears to fade smoothly. Now physicists have watched a microscopic resonator lose its final phonon in real time, jumping abruptly from one quantum of vibration to none.

A superconducting qubit followed a nanomechanical resonator from its one-phonon state to the ground state, revealing a discrete jump while also exposing the readout's own back-action.