  Quantum information science and intense laser matter interaction are two
apparently unrelated fields. Here, we introduce the notion of quantum
information theory to intense laser driven processes by providing the quantum
mechanical description of measurement protocols for high harmonic generation in
atoms. This allows to conceive new protocols for quantum state engineering of
light. We explicitly evaluate conditioning experiments on individual optical
field modes, and provide the corresponding quantum operation for coherent
states. The associated positive operator-valued measures are obtained, and give
rise to the quantum theory of measurement for the generation of high
dimensional entangled states, and coherent state superposition with
controllable non-classical features on the attosecond timescale. This establish
the use of intense laser driven processes as a novel quantum technology
platform for quantum information processing.
