Figure 3
From: Hybrid setup for stable magnetic fields enabling robust quantum control
Measurements of superposition-state coherence times via Ramsey spectroscopy. (a) As an example, we show the variation of state population P|3,1〉 as a function of relative (microwave) phase Δϕ between two π/2 pulses, that are separated by TRamsey = 0.001 s (
) and 1.0 s (
); error bars correspond to statistical uncertainties (s.e.m.). Sinusoidal model fits to both data give best values for the achieved contrast of 0.948(7) and 0.86(4), respectively. (b) Evolution of contrast normalized to the initial contrast for four different sets of internal state superpositions using states |3,1〉 -|2,0〉 (
), |2,1〉 -|2,2〉 (
), |3,1〉 -|2,2〉 (
), and |3,3〉 -|2,2〉 (
), as a function of TRamsey; error bars indicate s.e.m.. Individual fits of exponential decays to each data set yield coherence times τ, defined as the duration where contrast reaches a level of e−1. We find corresponding durations of 6.6(0.9) s (
), 0.0018(2) s (
), 0.0009(1) s (
), and 0.00042(6) s (
) for the four different superposition states, respectively.
