slew (2918) writes "Although electrons are usually thought of having 2 properties: spin and charge, bound electrons actually have a 3rd quantum property related to their so-called orbit's angular momentum. Spinon and holon quasi-particles have been observed before which represent the spin and charge quantum values of the electron. Now this experiment takes advantage of the fact that nominally bound electrons can delocalize in a lattice into energy bands and make it possible to measure the effect of the orbiton quasi-particles (which has the value of the electron's angular momentum where it was originally nominally bound, even though now delocalized). Hope that made some sense..."
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