  We consider a symmetric gap plasmon guide (a folded Kretschmann
configuration) supporting both symmeric and antisymmetric coupled surface
plasmons. We calculate the transverse spin under illumination from both the
sides like in coherent perfect absorption (CPA), whereby all the incident light
can be absorbed to excite one of the modes of the structure. Significant
enhancement in the transverse spin is shown to be possible when the CPA dip and
the mode excitation are at the same frequency. The enhancement results from
CPA-mediated total transfer of the incident light to either of the coupled
modes and the associated large local fields. The transverse spin is localized
in the structure since in the ambient dielectric there are only incident plane
waves lacking any structure.
