Hello PFers! I hope everyone is doing well. Here's my question: The way I understand it (imperfectly, of course), forward-biasing a p-n junction diode, the electrons crossover from the n-type material and fall into the holes in the p-type material and then they are conducted through the holes in the valence band. This current in the p-type, I presume, is hole current. But if the holes are being filled by electrons from the other side, wouldn't this recombination process deplete charge carriers, impeding some current flow? Also if a hole is filled, so that an atom is "complete", could a neighboring hole still migrate into the "filled" atom? I mean there would be no vacancy left for migration to occur, so how does it all work? I am also interested in knowing how an isolated p-type material would behave when applied a potential difference. Is it any different from how the p-type side behaves in a p-n junction diode (for example, does recombination take place?). Thank you very much for your time!