Continuous-time hybridization expansion quantum impurity solver for   multi-orbital systems with complex hybridizations
  We describe an open-source implementation of the continuous-time hybridization-expansion quantum Monte Carlo method for impurity models with general instantaneous two-body interactions and complex hybridization functions. The code is built on the ALPS libraries (Applications and Libraries for Physics Simulations). 
Hiroshi Shinaoka, Emanuel Gull, Philipp Werner
cond-mat.str-el