Fig. 2

Mollow absorption. a A weak probe with phase orthogonal to a strong drive field drives the sideband transition at ω = ω ₀ ± Ω. Measurements were performed on an NV center with optical initialization and readout (green laser pulses). The duration of the drive (~1.3 μs) was adjusted for every drive field power Ω (set by the microwave power P _drive) to correspond to an integer number of π rotations. b A weak probe in phase with the strong drive field drives the central transition ω ₀