Fig. 7: Population transfer scheme for ramsey interferometry.

729 nm laser pulses on the computational ion used for Ramsey interferometry, executed from left to right. The experiment is comprised of three sets of pulses, (a) preparation, (b) echo and (c) analysis, described in Box 1. Circles indicate the ion state population before and after each set of pulses. The filled circle represents complete population in the \(\left\vert -1/2\right\rangle\) state. Half circles indicate 50/50 superpositions between the \(\left\vert+1/2\right\rangle,\: \left\vert -1/2\right\rangle\) states. Population swaps between these two states during the echo sequence. Hashed circles represent a superposition of the \(\left\vert -1/2\right\rangle\) and \(\left\vert D\right\rangle\) states.