  In contradistinction with some plausible statements of the information
theory, we point out the possibility of the zero energy quantum information
processing. Particularly, we investigate the rate of the entanglement formation
in the operation of the quantum "oracles" employing the "quantum parallelism",
and we obtain that the relative maximum of the rate of the operation
distinguishes the zero average energy of interaction in the composite system
"input register + output register". This result is reducible to neither of the
previously obtained bounds, and therefore represents a new bound for the
nonorthogonal state transformations in the quantum information theory.
