The hybridization-expansion segment solver

The TRIQS-based hybridization-expansion segment solver allows to solve the problem of a quantum impurity embedded in a conduction bath. It is restricted to purely density-density interaction vertices, but is very much optimized for this situation. Moreover, these interactions may be dynamical in the charge and longitudinal spin channel (even in a multiorbital context), as well as in the transverse spin channel (only for a single-orbital model). Finally, the code supports off-diagonal hybridization terms.

The code can be used both in C++ and Python to measure the one-particle Green’s function, density-density correlation functions, three- and four-point correlation functions (and the corresponding vertices), various improved estimators corresponding to these correlation functions, as well as various histograms.

You can learn how to use it in the documentation:

To install the code, report issues or get more information, check out:

Note

For impurity models with static, non-density-density interactions and/or static hopping terms on the impurity, we refer the user to the TRIQS/cthyb (https://triqs.github.io/cthyb) solver.