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 (1D) 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 1D disordered Bose–Hubbard model at unit filling. (paper)