Stochastic vector computational approaches for the electronic structure of extended condensed matter systems help reduce algorithmic complexity, facilitate efficient parallelization, simplify computational tasks, accelerate calculations, and diminish memory requirements. The electronic density is estimated by a stochastic process that samples the Kohn-Sham eigenstate contribution according to...
We developed a stochastic density functional theory (sDFT) approach under a nonorthogonal , atom-centered basis set representation. The method is a highly parallelizable linear-scaling approach in which the reduced scaling is achieved without imposing (or relying on) a sparse structure to the Kohn-Sham density matrix, and as such may be applicable to a wide variety of systems in biology and...
We will present a massively parallel DFT approach which doesn’t rely on electron localization and is formally quadratic scaling yet enables highly efficient linear wall-time complexity in the weak scalability regime. The method extends from the stochastic DFT approach described in Fabian et al. WIRES: Comp. Mol. Science, e1412 2019 but is entirely deterministic and is well suited for the warm...
Accurately modeling dense plasmas over wide ranging conditions of pressures and temperatures is a grand challenge problem critically important to our understanding of inertial confinement fusion (ICF), stellar physics, exoplanets, and planetary formation. Over the last few years planewave- based Kohn-Sham Density Functional Theory Molecular Dynamics (DFT-MD) has proven highly successful in...
We present an extensive description of the application of a generalized collective modes model to ab initio simulations in the warm dense matter regime. We calculate the intermediate scattering function for warm dense aluminum by using density functional theory molecular dynamics simulations. From this data set we derive the static and dynamic ion-ion structure factors. Applying a generalized...
Average-atom (AA) models are an important tool in the modelling of warm dense matter, being both a computationally cheap and conceptually straightforward alternative to full DFT MD simulations. AA models are typically based on a common premise - namely, an atom immersed in a plasma environment - but use a range of different assumptions and approximations, which can cause inconsistent...
The simulation of correlated fermions is important for various phenomena in warm dense matter, plasmonics, and ultracold atoms. In order to enable simulations at larger length and longer time scales, there is a need to develop quantum hydrodynamics (QHD) as a complementary method to commonly used first-principles methods. The key difference of the QHD from classical fluid equations is the...
