Figure 2 : Experimental data from the Bragg gravity gradiometers.

From: Quantum test of the equivalence principle for atoms in coherent superposition of internal energy states

Figure 2

(left) With both atomic samples prepared in the F=1 state (1−1 configuration, black squares), and with the upper sample in F=1 and the lower sample in a coherent superposition of the two hyperfine states (1−s configuration, blue triangles). (right) With both atomic samples prepared in the F=1 state (1−1 configuration, black squares), and with the upper sample in F=1 and the lower sample in F=2 (1−2 configuration, blue triangles). The ellipses best fitting the experimental data are also shown (red lines). The loss of contrast observed on the interferometer can be attributed to the defocusing effect experienced by the atoms when interrogated by the blue-detuned Bragg lasers.