Assume you have two parallel plates with charges +q and -q. Now, you fill the space in between with two different dielectrics so that if you were to move straight from one plate to the other, you would be in the same dielectric. (In other words, the two dielectrics do not form "layers.") My question is: What happens to the charges on the plates? Do they stay uniformly distributed? This would mean the potential difference across the capacitor is different at different locations. Wouldn't this make the electric field inside the capacitor non-conservative? Do the charges move reposition themselves so that the potential difference remains constant? If this were true, wouldn't the charges have a tendency to go back to uniform distribution because the closer-packed ones would repel each other more? If the capacitor is connected to an EMF source with constant voltage, then I believe the charges would reposition themselves to maintain the same potential drop. But what if there is no current?