RT Journal Article
SR Electronic
T1 Deconfined Quantum Critical Points
JF Science
JO Science
FD American Association for the Advancement of Science
SP 1490
OP 1494
DO 10.1126/science.1091806
VO 303
IS 5663
A1 Senthil, T.
A1 Vishwanath, Ashvin
A1 Balents, Leon
A1 Sachdev, Subir
A1 Fisher, Matthew P. A.
YR 2004
UL http://science.sciencemag.org/content/303/5663/1490.abstract
AB The theory of second-order phase transitions is one of the foundations of modern statistical mechanics and condensed-matter theory. A central concept is the observable order parameter, whose nonzero average value characterizes one or more phases. At large distances and long times, fluctuations of the order parameter(s) are described by a continuum field theory, and these dominate the physics near such phase transitions. We show that near second-order quantum phase transitions, subtle quantum interference effects can invalidate this paradigm, and we present a theory of quantum critical points in a variety of experimentally relevant two-dimensional antiferromagnets. The critical points separate phases characterized by conventional “confining” order parameters. Nevertheless, the critical theory contains an emergent gauge field and “deconfined” degrees of freedom associated with fractionalization of the order parameters. We propose that this paradigm for quantum criticality may be the key to resolving a number of experimental puzzles in correlated electron systems and offer a new perspective on the properties of complex materials.