Figure 1
Illustration: Alan Stonebraker

Figure 1: Schematic phase diagram with two very different spin configurations. At the deconfined quantum critical point gc, the NĂ©el order parameter O1 and the valence bond crystal order parameter O2 vanish continuously from the two sides and spin-1/2 excitations (shown in inset as a free spin in a sea of singlet pairs) become deconfined. At this point, free spinons and photons emerge as dynamical variables in the system.