This award supports theoretical research to explore a possible explanation for highly anisotropic metallic states revealed in experiments on high quality quantum Hall systems, and a possible mechanism for producing non-Fermi liquid metallic states. The proposed research has four aims: (1) to develop quantitative models of stripes that allow one to assess what kind of ordering is really present at low temperatures when fluctuations are included; (2) to understand how this system might avoid localization (Fermi liquid) and pinning (charge density wave); (3) to understand the transition between bubbles and stripes, particularly when disorder is present, and to search for new pinning behavior and possibly glassy behavior in these unusual systems; and (4) to explore new physics associated with interlayer phase coherence when a second layer is introduced. Various field theoretical techniques, numerical simulations, and renormalization group methods will be used to carry out the research. %%% This award supports theoretical research that pursues a possible explanation of exotic metallic states of electrons confined to two-dimensions and layers of such electrons. The research will focus on unusual metallic states that have been observed in experiments on quantum Hall systems. It is supposed that in these systems electrons participate in novel bubble phases and striped phases that are analogous to phases found in liquid crystals. Because of the good theoretical tools available for studying quantum Hall systems, these may prove to be a controlled proving ground for exploring striped phases more generally. The study of striped quantum Hall phases may illuminate the origins of unusual metallic states and striped phases observed in the high temperature superconductors. The award will support postdoctoral training in state-of-the-art methods in condensed matter theory. ***
