Projects
Quantum Monte Carlo for strongly correlated electronic systemsSupervisor:
Ing. Matúš Dubecký, PhD.
This page shows details on the project. The primary projects are displayed together with a list of sub-projects.
| Project description: | In recent years, single-determinant fixed-node diffusion Monte Carlo (FNDMC) reached high-standard accuracy
in a number of diverse systems (where mean-field methods like DFT do not suffice) ranging from weakly bound
noncovalent complexes to strongly correlated systems like solid transition-metal oxides at high pressures.
Thanks to its favourable CPU cost scaling, parallelism, and direct access to periodicity, FNDMC gains popularity
as an unprecedented benchmark tool for large realistic complex many-electron systems.
Recent results however suggest, that the expected accuracy is not always accessible, sometimes the results are
overvalued, or they depend on the parameters that have been ignored to date. The reason being incomplete
understanding of FN approximation (FNA) and its interplay with other possible biases.
Our goal is identification and development of deep conceptual understanding of the key FNDMC error sources in
strong interaction limit.
We plan to uncover the currently unknown links between generic nodal (position-space) properties (e.g.,topology) of fermionic wave functions, and, their connection to the structure of many-determinant expansions
and 1-particle reduced density matrix occupation numbers, as well as separation of electron correlation energy to
dynamic and nondynamic (strong, multireference) component, which will enable fundamental understanding of
FNA limits and decoupling of FN-bias from other bias sources of FNDMC. We also plan screening of FNDMC
accuracy in strongly interacting model systems and unprecedented method developments that go beyond FN
approximation.
In addition to deep physical insights to the strong correlation effects in complex many-electron systems and limits
of FNDMC methodology, the results of the project will enable rational usage and fine bias control of this method
valuable for large systems. |
| Kind of project: | APVV - Všeobecná výzva () |
| Department: | Advanced Technologies Research Institute (MTF) |
| Project identification: | APVV-18-0161 |
| Project status: | In process of execution |
| Project start date : | 01. 07. 2019 |
| Project close date: | 30. 06. 2023 |
| Number of workers in the project: | 4 |
| Number of official workers in the project: | 4 |
Official project workersThe following table shows the researcher workers who have been assigned official roles in a project.