Lamb Dicke regime

In ion trapping and atomic physics experiments, the Lamb Dicke regime (or Lamb Dicke limit) is a quantum regime in which the coupling (induced by an external light field) between an ion or atom's internal qubit states and its motional states is sufficiently small so that transitions that change the motional quantum number by more than one are strongly suppressed.

This condition is quantitively expressed by the inequality

where is the Lamb–Dicke parameter and is the motional quantum number of the ion or atom's harmonic oscillator state.