  We investigate coherent perfect absorption (CPA) in quantum optics, in
particular when pairs of squeezed coherent states of light are superposed on an
absorbing beam splitter. First, by employing quantum optical input-output
relations, we derive the absorption coefficients for quantum coherence and for
intensity, and reveal how these will differ for squeezed states. Secondly, we
present the remarkable properties of a CPA-gate: two identical but otherwise
arbitrary incoming squeezed coherent states can be completely stripped off
their coherence, producing a pure entangled squeezed vacuum state that with its
finite intensity escapes from an otherwise perfect absorber. Importantly, this
output state of light is not entangled with the absorbing beam splitter by
which it was produced. Its loss-enabled functionality makes the CPA gate an
interesting new tool for continuous-variable quantum state preparation.
