It has recently been proposed that insulators with large band gaps and strong spin-orbit coupling can host a new phase of quantum matter called a topological insulator that is characterized by entangled wavefunctions. The proposal has now been realized by an international collaboration led by researchers from Princeton University who studied the electronic structure of insulating alloys of bismuth and antimony by means of angle-resolved photoemission spectroscopy (ARPES) and spin-resolved ARPES. Read more »