  Molecular ro-vibronic coherences, joint energy-time distributions of quantum
amplitudes, are selectively prepared, manipulated, and imaged in
Time-Frequency-Resolved Coherent Anti-Stokes Raman Scattering (TFRCARS)
measurements using femtosecond laser pulses. The studies are implemented in
iodine vapor, with its thermally occupied statistical ro-vibrational density
serving as initial state. The evolution of the massive ro-vibronic
superpositions, consisting of 1000 eigenstates, is followed through
two-dimensional images. The first- and second-order coherences are captured
using time-integrated frequency-resolved CARS, while the third-order coherence
is captured using time-gated frequency-resolved CARS. The Fourier filtering
provided by time integrated detection projects out single ro-vibronic
transitions, while time-gated detection allows the projection of arbitrary
ro-vibronic superpositions from the coherent third-order polarization. Beside
the control and imaging of chemistry, the controlled manipulation of massive
quantum coherences suggests the possibility of quantum computing. We argue that
the universal logic gates necessary for arbitrary quantum computing - all
single qubit operations and the two-qubit controlled-NOT (CNOT) gate - are
available in time resolved four-wave mixing in a molecule. The molecular
rotational manifold is naturally "wired" for carrying out all single qubit
operations efficiently, and in parallel. We identify vibronic coherences as one
example of a naturally available two-qubit CNOT gate, wherein the vibrational
qubit controls the switching of the targeted electronic qubit.
