Crystal Defects Interact to Form Intricate Structures

S ystemsmade from ordered components, such as crystals, are often laced with defects, such as dislocations, where the ordering is disrupted. Researchers have now identified a new class of such flaws where two or more dislocations come together and become locked into complex geometrical arrangements, such as coils or knots, that can’t be smoothed away [1]. Using microscopy experiments backed up by theoretical arguments, they have identified such coiled “metadefects” in thin films of liquid