Ph.D. Thesis - Physics

Figure 5-3: Fit to Eq. 5.2 of the CPO computed pseudopotential in the ˆz direction at the
center of one well. The plot is of potential as a function of height; the z = 0 plane is located
at the potential minimum, approximately 0.18 mm above the trap electrode. The fit was
done only near the center of the well, where the trap is approximately harmonic. Fitting
the function at larger z values would require additional terms in the expansion of Eq. 5.2,
but since we are most interested in the potential at the trap center, we do not do this. The
fit yields r1 = 3.1 ± 0.1 mm, α = −4.0 ± 1.3, and z1 = 19 mm. Note that the experimental
parameters used are those for the macroions (Sec. 5.5), not atomic ions (Sec. 5.4).
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