Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Linear Paul trap design for an optical clock with Coulomb crystals   We report on the design of a segmented linear Paul trap for optical clock
applications using trapped ion Coulomb crystals. For an optical clock with an
improved short-term stability and a fractional frequency uncertainty of 10^-18,
we propose 115In+ ions sympathetically cooled by 172Yb+. We discuss the
systematic frequency shifts of such a frequency standard. In particular, we
elaborate on high precision calculations of the electric radiofrequency field
of the ion trap using the finite element method. These calculations are used to
find a scalable design with minimized excess micromotion of the ions at a level
at which the corresponding second- order Doppler shift contributes less than
10^-18 to the relative uncertainty of the frequency standard.

7
The categories of this paper are: hep-th
25
The categories of this paper are: patt-sol
19
The categories of this paper are: eess
37
The categories of this paper are: supr-con
34
The categories of this paper are: chem-ph
4
The categories of this paper are: cond-mat
22
The categories of this paper are: chao-dyn
20
The categories of this paper are: acc-phys
9
The categories of this paper are: nlin
6
The categories of this paper are: astro-ph
11
The categories of this paper are: hep-lat
31
The categories of this paper are: ao-sci
15
The categories of this paper are: nucl-ex
28
The categories of this paper are: alg-geom
21
The categories of this paper are: adap-org
18
The categories of this paper are: econ