  We present a tapered Paul trap whose radio frequency electrodes are inclined
to the symmetric axis of the endcap electrodes, resulting in a funnel-shaped
trapping potential. With this configuration, a charged particle confined in
this trap has its radial degrees of freedom coupled to that of the axial
direction. The same design was successfully used to experimentally realize a
single-atom heat engine, and with this setup amplification of zeptonewton
forces was implemented. In this paper, we show the design, implementation, and
characterization of such an ion trap in detail. This system offers a high level
of control over the ion's motion. Its novel features promise applications in
the field of quantum thermodynamics, quantum sensing, and quantum information.
