89 citations · 163 across the 29 of their papers we have counts for
31 papers
Kinetic energy from the cubic sum rule of the dynamic structure factor
Fotios Kalkavouras, Panagiotis Tolias, Sebastian Schwalbe +6
The third frequency moment sum rule of the dynamic structure factor is explored for the first time as an alternative estimator of the kinetic energy of quantu…
X-Ray Diagnostics Analysis Verification and Exploration (xDAVE) Code for the Prediction and Interpretation of X-Ray Thomson Scattering Experiments
Hannah M. Bellenbaum, Dave A. Chapman, Maximilian P. Böhme +8
X-ray Thomson scattering (XRTS) is a common diagnostic used in the warm dense matter (WDM) regime to estimate plasma parameters like density, temperature and charge state. Experime…
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…
Unlocking the Power of Orbital-Free Density Functional Theory to Explore the Electronic Structure Under Extreme Conditions
Cheng Ma, Qiang Xu, Zhenhao Zhang +8
Recent advances in X-ray free-electron laser diagnostics have enabled direct probing of the electronic structure under extreme pressures and temperatures, such as those encountered…
Generalized density functional theory framework for the non-linear density response of quantum many-body systems
Zhandos A. Moldabekov, Cheng Ma, Xuecheng Shao +5
A density functional theory (DFT) framework is presented that links functional derivatives of free-energy functionals to non-linear static density response functions in quantum man…
The noiseless limit and improved-prior limit of the maximum entropy method and their implications for the analytic continuation problem
Thomas Chuna, Nicholas Barnfield, Paul Hamann +3
Quantum Monte Carlo (QMC) methods are uniquely capable of providing exact simulations of quantum many-body systems. Unfortunately, the applications of a QMC simulation are limited…
Spectral Deconvolution without the Deconvolution: Extracting Temperature from X-ray Thomson Scattering Spectra without the Source-and-Instrument Function
Thomas Gawne, Alina Kononov, Andrew Baczewski +7
X-ray Thomson scattering (XRTS) probes the dynamic structure factor of the system, but the measured spectrum is broadened by the combined source-and-instrument function (SIF) of th…
Enhancing the Efficiency of Time-Dependent Density Functional Theory Calculations of Dynamic Response Properties
Zhandos A. Moldabekov, Sebastian Schwalbe, Uwe Hernandez Acosta +4
X-ray Thomson scattering (XRTS) constitutes an essential technique for diagnosing material properties under extreme conditions, such as high pressures and intense laser heating. Ti…
Correlation function metrology for warm dense matter: Recent developments and practical guidelines
Maximilian Peter Böhme, Willow Martin, Hannah Bellenbaum +13
X-ray Thomson scattering (XRTS) has emerged as a valuable diagnostic for matter under extreme conditions, as it captures the intricate many-body physics of the probed sample. Recen…
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…
Orientational Effects in the Low Pair Continuum of Aluminium
Thomas Gawne, Zhandos A Moldabekov, Oliver S Humphries +6
We compare the predictions of the dynamic structure factor (DSF) of ambient polycrystalline aluminium from time-dependent density functional theory (TDDFT) in the pair continuum re…
Ab initio density functional theory approach to warm dense hydrogen: from density response to electronic correlations
Zhandos A. Moldabekov, Xuecheng Shao, Hannah M. Bellenbaum +5
Understanding the properties of warm dense hydrogen is of key importance for the modeling of compact astrophysical objects and to understand and further optimize inertial confineme…
Static linear density response from X-ray Thomson scattering measurements: a case study of warm dense beryllium
Sebastian Schwalbe, Hannah Bellenbaum, Tilo Döppner +8
Linear response theory is ubiquitous throughout physics and plays a central role in the theoretical description of warm dense matter -- an extreme state that occurs within compact…
Applying the Liouville-Lanczos Method of Time-Dependent Density-Functional Theory to Warm Dense Matter
Zhandos A. Moldabekov, Sebastian Schwalbe, Thomas Gawne +3
Ab initio modeling of dynamic structure factors (DSF) and related density response properties in the warm dense matter (WDM) regime is a challenging computational task. The DSF, co…
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…
HEART: A New X-Ray Tracing Code for Mosaic Crystal Spectrometers
Thomas Gawne, Sebastian Schwalbe, Thomas Chuna +3
We introduce a new open-source Python x-ray tracing code for modelling Bragg diffracting mosaic crystal spectrometers: High Energy Applications Ray Tracer (HEART). HEART's high mod…
Fermionic free energies from \textit{ab initio} path integral Monte Carlo simulations of fictitious identical particles
Tobias Dornheim, Zhandos Moldabekov, Sebastian Schwalbe +2
We combine the recent ensemble path integral Monte Carlo (PIMC) approach to the free energy [T.~Dornheim \textit{et al.}, \textit{Phys.~Rev.~B} \textbf{111}, L041114 (2025)] wi…
Strong geometry dependence of the X-ray Thomson Scattering Spectrum in single crystal silicon
Thomas Gawne, Zhandos A. Moldabekov, Oliver S. Humphries +17
We report on results from an experiment at the European XFEL where we measured the x-ray Thomson scattering (XRTS) spectrum of single crystal silicon with ultrahigh resolution. Com…
Chemical potential of the warm dense electron gas from ab initio path integral Monte Carlo simulations
Tobias Dornheim, Michael Bonitz, Zhandos Moldabekov +3
We present extensive new \emph{ab initio} path integral Monte Carlo (PIMC) simulation results for the chemical potential of the warm dense uniform electron gas (UEG), spanning a br…
Model-free Rayleigh weight from x-ray Thomson scattering measurements
Tobias Dornheim, Hannah M. Bellenbaum, Mandy Bethkenhagen +16
X-ray Thomson scattering (XRTS) has emerged as a powerful tool for the diagnostics of matter under extreme conditions. In principle, it gives one access to important system paramet…
Direct free energy calculation from ab initio path integral Monte Carlo simulations of warm dense matter
Tobias Dornheim, Zhandos Moldabekov, Sebastian Schwalbe +1
We carry out highly accurate \emph{ab initio} path integral Monte Carlo (PIMC) simulations to directly estimate the free energy of various warm dense matter systems including the u…
First principles simulations of dense hydrogen
Michael Bonitz, Jan Vorberger, Mandy Bethkenhagen +24
Accurate knowledge of the properties of hydrogen at high compression is crucial for astrophysics (e.g. planetary and stellar interiors, brown dwarfs, atmosphere of compact stars) a…
Ab initio Density Response and Local Field Factor of Warm Dense Hydrogen
Tobias Dornheim, Sebastian Schwalbe, Panagiotis Tolias +3
We present quasi-exact ab initio path integral Monte Carlo (PIMC) results for the partial static density responses and local field factors of hydrogen in the warm dense matter regi…