262 citations · 4.3k across the 149 of their papers we have counts for
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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…
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…
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…
A Momentum-Resolved X-ray Thomson Scattering Benchmark of Electronic-Response Models in Warm Dense Aluminium
Dmitrii S. Bespalov, Ulf Zastrau, Zhandos A. Moldabekov +58
The robust diagnosis of conditions generated in warm dense matter (WDM) experiments remains a persistent challenge. Here we describe the measurement of shock-compressed aluminium a…
Reweighting scheme for the calculation of grand-canonical expectation values in quantum Monte Carlo simulations with a fermion sign problem
Paul Hamann, Jan Vorberger, Tobias Dornheim
Ab initio path integral Monte Carlo (PIMC) simulations constitute the gold standard for the estimation of a broad range of equilibrium properties of a host of interacting quantum m…
Kinetic contribution to the arbitrary order odd frequency moments of the dynamic structure factor
Panagiotis Tolias, Tobias Dornheim, Jan Vorberger
An exact expression is derived for the kinetic contribution to the odd (arbitrary order) frequency moments of the dynamic structure factor via a finite summation that features aver…
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…
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…
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…
Exact series expansion for even frequency moments of the dynamic structure factor
Panagiotis Tolias, Jan Vorberger, Tobias Dornheim
An exact series representation of the even frequency moments of the dynamic structure factor is derived. Truncations are proposed that allow to evaluate the explicitly unknown seco…
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…
PyLIT: Reformulation and implementation of the analytic continuation problem using kernel representation methods
Alexander Benedix Robles, Phil-Alexander Hofmann, Thomas Chuna +2
Path integral Monte Carlo (PIMC) simulations are a cornerstone for studying quantum many-body systems. The analytic continuation (AC) needed to estimate dynamic quantities from the…
Roadmap for warm dense matter physics
Jan Vorberger, Frank Graziani, David Riley +71
This roadmap presents the state-of-the-art, current challenges and near future developments anticipated in the thriving field of warm dense matter physics. Originating from strongl…
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…
Application of a spherically averaged pair potential in \emph{ab initio} path integral Monte Carlo simulations of the warm dense electron gas
Tobias Dornheim, Thomas M. Chuna, Hannah M. Bellenbaum +3
Spherically averaged periodic pair potentials offer the enticing promise to provide accurate results at a drastically reduced computational cost compared to the traditional Ewald s…
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…
Estimates of the dynamic structure factor for the finite temperature electron liquid via analytic continuation of path integral Monte Carlo data
Thomas Chuna, Nicholas Barnfield, Jan Vorberger +3
Understanding the dynamic properties of the uniform electron gas (UEG) is important for numerous applications ranging from semiconductor physics to exotic warm dense matter. In thi…
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…