- #1
Malamala
- 299
- 27
Hello! Assume we have a simple harmonic oscillator potential, in 3D (say created by some electric fields, such as a Paul trap) and inside it we have a 2 level system in the excited state (say an ion in which we care only about 2 levels, for example the lowest 2). The translational energy of the ion can change only if the difference is given by the frequency difference between the levels of the harmonic oscillator, ##\omega_{osc}##. However, when we have a decay from the excited state, the atom will achieve a given kinetic energy, in order to conserve the momentum (this is the principle behind the Doppler cooling of ions/atoms). Can the transition frequency ##\omega_{ion}## be such that the ion will be forever stuck in the excited state, just because it can't achieve a recoil energy that is a multiple of ##\omega_{osc}##?