0705048_Friedman

1. Entanglement Entropy of Random Hall SystemsBarry A. Friedman, Sam Houston State University, DMR 0705048 In experiment, disorder has an important effect on quantum Hall states. In particular, the fractional quantum Hall state at filling 5/2, the best candidate for a system with non-abelian statistics, is very sensitive to disorder. However, numerically, with accessible system sizes, and conventional observables, it is difficult to see the effect of disorder. The figure is a plot of the entanglement entropy for a subsystem of 12 orbitals vs. disorder strength for filling 5/2. Despite the small number of electrons (10-13) there is a clear signature of a transition at a disorder strength approximately equal .04. An interpretation of this transition is the destruction of the Moore-Read state by disorder.

2. Simulation of a Near Field Microwave Microscope Barry A. Friedman, Sam Houston State University, DMR 0705048 A broader impact is the education and training of students. Shown are masters student Darwin Luna and undergraduate student Curtis Balusek. They are explaining COMSOL multiphysics to the Principle Investigator. A near field scanning microwave microscope (NSMM) is being simulated using the finite element method. Recently, Agilent has commercialized a NSMM for application to the semiconductor industry.