Fig. 3: Exchange cooling calibration and performance.
(a) Oscillations in axial mode temperature \(\overline{n}\) following exchange transport as a function of tex. Energy swaps between the computational ion (red) and the coolant ion (blue). Our procedure for determining \(\overline{n}\) and its uncertainty using a fixed-length sideband pulse is described in Temperature Measurements. Solid lines are simulations, as described in Ion Motional Simulations. (b) Computational ion temperature after exchange transport as the initial temperature is varied, along with a linear fit (solid black line). The blue arrow indicates the results of an experiment in which the coolant ion was re-cooled after the first exchange and a second exchange was attempted. Horizontal (vertical) error bars represent the uncertainty in ion temperature before (after) exchange transport measured using the sideband flopping method.
