M1L5i_CQ9.txt

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So we have exactly the same situation.
We have our beam splitter.
We split our coherent beam into two teams exactly as before.
But now I'm playing with a vacuum.
I'm playing with the open part of the beams splitter.
And I put in squeezed vacuum.
And just to be specific, I've squeezed the vacuum
in such a way that what is narrow now
is the quadrature component of the coherent state.
In other words, the coherent state is cosine omega t.
In sine omega t, we haven't put in any photons.
Our coherent state has rarely an classical oscillation
in cosine omega t.
And what I've squeezed used here with the vacuum
is the noise in the cosine omega t quadrature component.
So in other words, the coherent state and the short exits
of the ellipse are the same quadrature component,
which means they can now interfere.
So the question is now the following.
We split the beam.
We have n over 2 photons here.
We have n over 2 there.
And what is now the result for the variance?

I formulated a condition up there,
which is this strong local oscillator condition.
You should assume if you get confused
that the local oscillator is very, very strong.
And if you have any doubts about some smaller terms,
just crank up the power and make sure
that it's really the local oscillator, which dominates,
which is the biggest number in all equations.
OK, so the reference is without squeezing the noise
or the variance in i1 was n over 2.
With n over 2 photons, Poisson statistics, this was n over 2.
The question is now, when we use squeezed light,
does the variance stay the same?
Does it go up?
Does it go down, or does it go to 0?