  The capacity to confine light into a small region of space is of paramount
importance in many areas of modern science. Here, we suggest a mechanism to
store a quantized "bit" of light - with a very precise amount of energy - in an
open core-shell plasmonic structure ("meta-atom") with a nonlinear optical
response. Notwithstanding the trapped light state is embedded in the radiation
continuum, its lifetime is not limited by the radiation loss. Interestingly, it
is shown that the interplay between the nonlinear response and volume plasmons
enables breaking fundamental reciprocity restrictions, and coupling very
efficiently an external light source to the meta-atom. The collision of an
incident optical pulse with the meta-atom may be used to release the trapped
radiation "bit".
