TRIQS/CTHYB: A continuous-time quantum Monte Carlo hybridization expansion solver for quantum impurity problems

Priyanka Seth (1) , Igor Krivenko (2) , Michel Ferrero (1) , Olivier Parcollet (3)

1 X - École polytechnique
2 UHH - Universität Hamburg
3 IPHT - Institut de Physique Théorique - UMR CNRS 3681

We present TRIQS/CTHYB, a state-of-the art open-source implementation of the continuous-time hybridisation expansion quantum impurity solver of the TRIQS package. This code is mainly designed to be used with the TRIQS library in order to solve the self-consistent quantum impurity problem in a multi-orbital dynamical mean field theory approach to strongly-correlated electrons, in particular in the context of realistic calculations. It is implemented in C++ for efficiency and is provided with a high-level Python interface. The code is ships with a new partitioning algorithm that divides the local Hilbert space without any user knowledge of the symmetries and quantum numbers of the Hamilto-nian. Furthermore, we implement higher-order configuration moves and show that such moves are necessary to ensure ergodicity of the Monte Carlo in common Hamiltonians even without symmetry-breaking.

Domains: Physics [physics]

Priyanka Seth, Igor Krivenko, Michel Ferrero, Olivier Parcollet. TRIQS/CTHYB: A continuous-time quantum Monte Carlo hybridization expansion solver for quantum impurity problems. Computer Physics Communications, 2016, 200, pp.274-284. ⟨10.1016/j.cpc.2015.10.023⟩. ⟨cea-01232430⟩