About CTSEG

The TRIQS/ctseg solver has been written by N. Kavokine and O. Parcollet, with contributions from H. Lu and N. Wentzell. The authors thank T. Ayral and M. Ferrero for sharing their unpublished implementation of CTSEG, which served as an inspiration and a benchmark for the present implementation.

The hybridization expansion algorithm was originally developed in 2006 by Philipp Werner in the segment picture formulation [1] and later generalized to arbitrary local traces [2, 3]. Dynamical interactions was introduced later for density-density [4, 5] and spin-spin interactions [6,7], see Ref. [8] for a review.

References

[1] Continuous-Time Solver for Quantum Impurity Models
P. Werner, A. Comanac, L. de’ Medici, M. Troyer, A. J. Millis
Phys. Rev. Lett. 97, 076405 (2006)
[2] Hybridization expansion impurity solver: General formulation and application to Kondo lattice and two-orbital models
P. Werner, A. J. Millis
Phys. Rev. B 74, 155107 (2006)
[3] Quantum Monte Carlo impurity solver for cluster dynamical mean-field theory and electronic structure calculations with adjustable cluster base
K. Haule
Phys. Rev. B 75, 155113 (2007)
[4] Efficient Dynamical Mean Field Simulation of the Holstein-Hubbard Model
P. Werner, A. J. Millis
Phys. Rev. Lett. 99, 146404 (2007)
[5] Dynamical Screening in Correlated Electron Materials
P. Werner, A. J. Millis
Phys. Rev. Lett. 104, 146401 (2010)
[6] Spin-boson coupling in continuous-time quantum Monte Carlo
J. Otsuki
Phys. Rev. B 87, 125102 (2013)
[7] Double-expansion impurity solver for multiorbital models with dynamically screened 𝑈 and 𝐽
K. Steiner, Y. Nomura, P. Werner
Phys. Rev. B 92, 115123 (2015)
[8] Dynamical screening in correlated electron systems —- from lattice models to realistic materials
P. Werner, M. Casula
J. Phys.: Condens. Matter 28 383001 (2016)