I will present the CoQui [1] software package developed at the Flatiron Institute’s Center for Computational Quantum Physics. The overarching goal of CoQui is the development and implementation of perturbative, low-scaling approaches to the many-body problem for first-principles electronic structure. CoQui relies on the use of Interpolative Separable Density Fitting to generate compact factorizations of the coulomb interaction, achieving an efficient framework for ab-initio many-body perturbation theory (MBPT). The package implements finite temperature variants of GW at various levels of self-consistency (single shot, quasi-particle and fully self-consistent), as well as several downfolding frameworks based on cRPA. It can be used to generate ab-initio low-energy models of complex materials and molecular systems. The resulting models can be combined with accurate many-body methods to provide new avenues to understand correlated phenomena. As a concrete example, I will discuss an implementation of GW+EDMFT obtained by interfacing CoQui with the TRIQS [2] software package. The new capabilities pave the way for the application of ab-initio quantum embedding on complex systems.
[1] CoQui: https://github.com/AbInitioQHub/coqui
[2] TRIQS: https://github.com/TRIQS
About the speaker:
Miguel A. Morales Silva joined the Center for Computational Quantum Physics in 2021 as a Research Scientist. His research is focused on the development, implementation, and application of quantum Monte Carlo methods for the study of quantum many-body problems. His main goal is the development of predictive, parameter-free, first-principles methods for the study of strongly correlated materials. He is also interested in large-scale, high-performance computing. He received B.A. degrees in Physics and Mathematics in 2004 from the University of Puerto Rico at Mayaguez and a Ph.D. in Physics from the University of Illinois at Urbana-Champaign in 2009. After his Ph.D., Miguel was a postdoctoral research associate in Rice University during 2009-2010, before joining Lawrence Livermore National Laboratory as a Research Scientist between 2010-2021. Miguel has received various awards and recognitions including: NNSA Defense Programs Award of Excellence, LLNL Early and Mid-Career Recognition Program, MOSI Early Career Hispanic Scientist of the Year, and Presidential Early Career Award for Scientists and Engineers (PECASE).
