Quantum jump

In quantum mechanics, such jumps are associated with the non-unitary evolution of a quantum-mechanical system during measurement.

A quantum jump can be accompanied by the emission or absorption of photons; energy transfer during a quantum jump can also occur by non-radiative resonant energy transfer or in collisions with other particles.

Their statistics are Poissonian, and the time between jumps is exponentially distributed.

[1] The damping time constant (which ranges from nanoseconds to a few seconds) relates to the natural, pressure, and field broadening of spectral lines.

The larger the energy separation of the states between which the electron jumps, the shorter the wavelength of the photon emitted.

[2] This requires one strong and one weak transition to be excited (denoted

3 which causes an interruption of the photon emission as the electron gets shelved in state through application of light with frequency

The ion going dark is a direct observation of quantum jumps.

Grotrian diagram of a quantum 3-level system with characteristic transition frequencies, 12 and 13 , and excited state lifetimes 2 and 3
EMCCD camera and photomultiplier tube signals while driving quantum jumps on the 674 nm transition of 88 Sr +