M3L16ba.txt

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I mentioned the two leaders of the field
are Gerhard Rempe and Jeff Kimble.
Well, Gerhard Rempe-- I actually did my--
he did his PhD in the same group,
at the same time, as I did, so I know him very well.
Then he went as a post-doc work with Jeff Kimble.
And now, as the director of the Max Planck Institute.
He has a world leading group in cavity QED.
Here, the two leaders have a joint paper,
which is the first observation of the vacuum Rabi
splitting in optical cavity.
Of course, you can easily observe it,
if you have a strong atomic beam with many atoms,
because then you have a good signal.
And secondly, the splitting is large and easily resolved.
So what they managed to do is, they managed to throttle down
the atomic beam, that fewer and fewer atoms, at a given time,
were in the cavity.
And eventually, they came down to the limit of one atom.
That was a historic experiment.
Of course, it's not perfect in the sense,
that you do not see the deep cut between the two peaks,
simply because, when on average you
have one atom in the cavity, sometimes you
have no atom in the cavity, and then you
will peak in the middle.
So those experiments in those days
were done only with average atom numbers,
and not with trapped atoms where you know for sure there's
exactly one atom in the cavity.
So, I don't show you an experiment,
but let me just state that this sort of single photon Rabi
flopping has been observed.
So you start with the cavity in the vacuum field,
and you sort of see this oscillation