197 citations · 1.6k across the 87 of their papers we have counts for
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Reweighting Estimators for Density Response in Path Integral Monte Carlo: Applications to linear, nonlinear and cross-species density response
Pontus Svensson, Thomas Chuna, Jan Vorberger +5
We present density response estimators for Monte Carlo simulations that are based on a reweighting procedure, where the samples of an unperturbed system are used to estimate the pr…
Van-der-Waals exchange-correlation functionals and their high pressure and warm dense matter applications
Jan Vorberger, Gabriel J. Smith, William Z. Van Benschoten +4
We investigate basic hydrogen quantities like the molecular bond length, the molecular dissociation energy and the van-der-Waals interaction in idealized situations in an effort to…
Taylor series perspective on ab initio path integral Monte Carlo simulations with Fermi-Dirac statistics
Tobias Dornheim, Alexander Benedix Robles, Paul Hamann +6
The fermion sign problem constitutes a fundamental computational bottleneck across a plethora of research fields in physics, quantum chemistry and related disciplines. Recently, it…
Re-weighting estimator for ab initio path integral Monte Carlo simulations of fictitious identical particles
Tobias Dornheim, Pontus Svensson, Paul Hamann +4
The fermion sign problem constitutes one of the most fundamental obstacles in quantum many-body theory. Recently, it has been suggested to circumvent the sign problem by carrying o…
Accelerated free energy estimation in ab initio path integral Monte Carlo simulations
Pontus Svensson, Fotios Kalkavouras, Uwe Hernandez Acosta +4
We present a methodology for accelerating the estimation of the free energy from path integral Monte Carlo simulations by considering an intermediate artificial reference system wh…
Second roton feature in the strongly coupled electron liquid
Thomas M. Chuna, Jan Vorberger, Panagiotis Tolias +5
We present extensive \emph{ab initio} path integral Monte Carlo (PIMC) results for the dynamic properties of the finite temperature uniform electron gas (UEG) over a broad range of…
Estimating ionization states and continuum lowering from ab initio path integral Monte Carlo simulations for warm dense hydrogen
Hannah M. Bellenbaum, Maximilian P. Böhme, Michael Bonitz +8
Warm dense matter (WDM) is an active field of research, with applications ranging from astrophysics to inertial confinement fusion. Ionization degree and continuum lowering are imp…
η-ensemble path integral Monte Carlo approach to the free energy of the warm dense electron gas and the uniform electron liquid
Tobias Dornheim, Panagiotis Tolias, Zhandos Moldabekov +1
We explore the recently introduced -ensemble approach to compute the free energy directly from \emph{ab initio} path integral Monte Carlo (PIMC) simulations [T.~Dornheim \emph{e…
Quantum delocalization, structural order, and density response of the strongly coupled electron liquid
Tobias Dornheim, Panagiotis Tolias, Jan Vorberger +1
We investigate the impact of electronic correlations and quantum delocalization onto the static structure factor and static density response function of the strongly coupled electr…
Ultrafast Heating Induced Suppression of -band Dominance in the Electronic Excitation Spectrum of Cuprum
Zhandos Moldabekov, Thomas D. Gawne, Sebastian Schwalbe +3
The combination of isochoric heating of solids by free electron lasers (FEL) and in situ diagnostics by X-ray Thomson scattering (XRTS) allows for measurements of material properti…
Ab initio path integral Monte Carlo simulations of the uniform electron gas on large length scales
Tobias Dornheim, Sebastian Schwalbe, Zhandos Moldabekov +2
The accurate description of non-ideal quantum many-body systems is of prime importance for a host of applications within physics, quantum chemistry, material science, and related d…
Bound state breaking and the importance of thermal exchange-correlation effects in warm dense hydrogen
Zhandos Moldabekov, Sebastian Schwalbe, Maximilian Böhme +5
Hydrogen at extreme temperatures and pressures is ubiquitous throughout our universe and naturally occurs in a variety of astrophysical objects. In addition, it is of key relevance…
Non-empirical mixing coefficient for hybrid XC functionals from analysis of the XC kernel
Zhandos A. Moldabekov, Mani Lokamani, Jan Vorberger +2
We present an analysis of the static exchange-correlation (XC) kernel computed from hybrid functionals with a single mixing coefficient such as PBE0 and PBE0-1/3. We break down the…
Assessing the accuracy of hybrid exchange-correlation functionals for the density response of warm dense electrons
Zhandos A. Moldabekov, Mani Lokamani, Jan Vorberger +2
We assess the accuracy of common hybrid exchange-correlation (XC) functionals (PBE0, PBE0-1/3, HSE06, HSE03, and B3LYP) within Kohn-Sham density functional theory (KS-DFT) for the…