Superfluid--Insulator Transition in Strongly Disordered One-dimensional   Systems
  We present an asymptotically exact renormalization-group theory of the superfluid--insulator transition in one-dimensional disordered systems, with emphasis on an accurate description of the interplay between the Giamarchi--Schulz (instanton--anti-instanton) and weak-link (scratched-XY) criticalities. Combining the theory with extensive quantum Monte Carlo simulations allows us to shed new light on the ground-state phase diagram of the one-dimensional disordered Bose-Hubbard model at unit filling. 
Zhiyuan Yao, Lode Pollet, Nikolay Prokof'ev and Boris Svistunov
cond-mat.str-el cond-mat.dis-nn cond-mat.stat-mech