Competition between point and columnar disorder on the behavior of flux   lines in 1+1 dimension
  The behavior of flux lines in the presence of both columnar and point disorder in 1+1 dimension is investigated using Renormalization Group and world-line Quantum Monte Carlo techniques. In particular, we calculate the transverse wandering correlation function for a single boson and recover known results for point and columnar disorder separately. We then examine the existence of a localization transition of a flux line in the simultaneous presence of both types of disorder. We also perform RG for interacting flux lines in the presence of both disorder. RG indicates that the vortex glass is unstable with respect to arbitrary small amount of columnar disorder. Using QMC we find that the Bose glass transition temperature is reduced by the point disorder, in agreement with recent RG calculations. Further we find that the region posited to be an Anderson glass is completely destroyed. 
T. P. Devereaux, R. T. Scalettar, and G. T. Zimanyi