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Consider the usual double slit experiment involving laser and a double slit and a screen. Now place in front of the left slit a quarter waveplate (let's call it QWP1) that changes a certain linear polarization (say, in the horizontal direction) into counterclockwise circular polarization. Now place another quarter waveplate (QWP2) in front of the right slit except QWP2 is sort of opposite of QWP1 in the sense that QWP2 changes the horizontal polarization into clockwise circular polarization, and the vertical polarization into counterclockwise circular polarization. In this new double slit experiment, will we see interference on the screen?

I am guessing that we will still see interference, but I just want to make sure I have right assumptions before I try to wrap my mind around this quantum eraser experiment exposition where they use entangled photons.

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No, you won't see interference. The cw and ccw states are orthogonal.

You can prove that intuitively in the following way. You could think of the incoming light to be cw polarized, then one waveplate would turn it vertical, the other one horizontal.

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What if the incoming light doesn't have any particular polarization? – Le Curious May 21 '13 at 18:26

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