One example from chemistry:
The HCl molecule is excited by the light with frequency n1
(Way 1). And simultaneously there is very intensive light with frequency
ν3
, having
ν1
= 3 · ν3. Thus the HCl
molecule is excited by three photon absorption in the same state but using
another Way 2. Frequencies ν1
and ν3 have the following particular phase
ratios:
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(It's not interesting for us now how one can obtain it.) And finally we
detect the HCl+-ions that are produced by HCl light excitation in the
j-state (each HCl(j) is transferred into HCl+). And if now we will
measure total ion yield with definite phase ratio, then it corresponds to the
electron yield which our detector has registered in previous examples of
electron dispersion in the point x (the phase ratio corresponds to electron
dispersion here). Therefore the phase ratio (but not the light intensity) change
shouldn't give rise to the ion yield alteration. The phase ratio can be readily
changed whereas both light beams ( ν1
and ν3) will have passed a long distance
through optical medium (here H2 gas) before they both ionize HCl
molecules.
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Simulation of HCl+ signals when HCl is excited by two indistinguishable ways having pressure alteration of H2 as the phase ratio changes. |
Since the refraction index n and therefore the travel time is different for different frequencies, the phase ratio is alternating between v1 and v3 during refraction index variation.
This variation of n can be reached by H2 pressure variation:
n − 1 ~ p |
As a result we will obtain the variation of HCl+ ion yield. However the intensities of both beams ν1 and ν2 stay constant! This is purely quantum-mechanical phenomenon which is based on the knowledge lack about the way the molecule has been excited.