The quantity Ω Ω 2 + δ δ 2 is commonly referred to as the "generalized Rabi frequency." For cases in which δ δ ≠ ≠ 0 , Rabi flopping actually occurs at this frequency, where δ δ is the detuning, a measure of how far the light is off-resonance relative to the transition. For instance, examining the above animation at an offset frequency of ±1.73, one can see that during the 1/2 Rabi cycle (at resonance) shown during the animation, the oscillation instead undergoes one full cycle, thus at twice the (normal) Rabi frequency Ω Ω i , j , just as predicted by this equation. Also note that as the incident light frequency shifts further from the transition frequency, the amplitude of the Rabi oscillation decreases, as is illustrated by the dashed envelope in the above plot.