- Open Access
Estimating ionization states and continuum lowering from ab initio path integral Monte Carlo simulations for warm dense hydrogen
Phys. Rev. Research 7, 033016 – Published 7 July, 2025
DOI: https://doi.org/10.1103/9d7r-1xbm
Abstract
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 important quantities to understand how materials behave under these conditions, but can be difficult to diagnose since experimental campaigns are limited and often require model-dependent analysis. This is especially true for hydrogen, which has a comparably low scattering cross section, making high-quality data particularly difficult to obtain. Consequently, building equation of state tables often relies on ab initio simulations in combination with untested approximations to extract properties from experiments. Here, we investigate an approach for extracting the ionization potential depression and ionization degree—quantities which are otherwise not directly accessible from the physical model—from first-principles path integral Monte Carlo (PIMC) simulations utilizing a chemical model. In contrast to experimental measurements, where noise and nonequilibrium effects add to the uncertainty of the inferred parameters, PIMC simulations provide a clean signal with well-defined thermodynamic conditions. Comparisons against commonly used models show a qualitative agreement, but we find deviations primarily for the high-density and high-temperature cases. We also demonstrate the decreasing sensitivity of the dynamic structure factor with respect to both ionization and continuum lowering for increasing scattering angles in x-ray Thomson scattering experiments. Our work has important implications for the design of future experiments, but also offers qualitative understanding of structure factors and the imaginary-time correlation function obtained from first-principles quantum Monte Carlo simulations.
Physics Subject Headings (PhySH)
Article Text
References (98)
- M. Bonitz, J. Vorberger, M. Bethkenhagen, M. P. Böhme, D. M. Ceperley, A. Filinov, T. Gawne, F. Graziani, G. Gregori, P. Hamann, S. B. Hansen, M. Holzmann, S. X. Hu, H. Kählert, V. V. Karasiev, U. Kleinschmidt, L. Kordts, C. Makait, B. Militzer, Z. A. Moldabekov et al., Toward first principles-based simulations of dense hydrogen, Phys. Plasmas 31, 110501 (2024).
- L. B. Fletcher, U. Zastrau, E. Galtier, E. J. Gamboa, S. Goede, W. Schumaker, A. Ravasio, M. Gauthier, M. J. MacDonald, Z. Chen, E. Granados, H. J. Lee, A. Fry, J. B. Kim, C. Roedel, R. Mishra, A. Pelka, D. Kraus, B. Barbrel, T. Döppner et al., High resolution x-ray Thomson scattering measurements from cryogenic hydrogen jets using the linac coherent light source, Rev. Sci. Instrum. 87, 11E524 (2016).
- M. S. Murillo, J. Weisheit, S. B. Hansen, and M. W. C. Dharma-wardana, Partial ionization in dense plasmas: Comparisons among average-atom density functional models, Phys. Rev. E 87, 063113 (2013).
- S. X. Hu, B. Militzer, V. N. Goncharov, and S. Skupsky, First-principles equation-of-state table of deuterium for inertial confinement fusion applications, Phys. Rev. B 84, 224109 (2011).
- D. I. Mihaylov, V. V. Karasiev, and S. X. Hu, Thermal hybrid exchange-correlation density functional for improving the description of warm dense matter, Phys. Rev. B 101, 245141 (2020).
- S. Faik, A. Tauschwitz, and I. Iosilevskiy, The equation of state package FEOS for high energy density matter, Comput. Phys. Commun. 227, 117 (2018).
- M. Bonitz, T. Dornheim, Z. A. Moldabekov, S. Zhang, P. Hamann, H. Kählert, A. Filinov, K. Ramakrishna, and J. Vorberger, Ab initio simulation of warm dense matter, Phys. Plasmas 27, 042710 (2020).
- T. Dornheim, M. Böhme, D. Kraus, T. Döppner, T. R. Preston, Z. A. Moldabekov, and J. Vorberger, Accurate temperature diagnostics for matter under extreme conditions, Nat. Commun. 13, 7911 (2022).
- S. H. Glenzer and R. Redmer, X-ray Thomson scattering in high energy density plasmas, Rev. Mod. Phys. 81, 1625 (2009).
- O. L. Landen, Probing dense plasmas for HEDS and ICF*, High Energy Density Phys. 51, 101102 (2024).
- T. Dornheim, P. Tolias, S. Groth, Z. A. Moldabekov, J. Vorberger, and B. Hirshberg, Fermionic physics from ab initio path integral Monte Carlo simulations of fictitious identical particles, J. Chem. Phys. 159, 164113 (2023).
- T. Dornheim, S. Schwalbe, Z. A. Moldabekov, J. Vorberger, and P. Tolias, Ab initio path integral Monte Carlo simulations of the uniform electron gas on large length scales, J. Phys. Chem. Lett. 15, 1305 (2024).
- T. Dornheim, T. Döppner, P. Tolias, M. Böhme, L. Fletcher, T. Gawne, F. Graziani, D. Kraus, M. MacDonald, Z. Moldabekov, S. Schwalbe, D. Gericke, and J. Vorberger, Unraveling electronic correlations in warm dense quantum plasmas, Nat. Commun. 16, 5103 (2025)
- D. M. Ceperley, Path integrals in the theory of condensed helium, Rev. Mod. Phys. 67, 279 (1995).
- T. Dornheim, S. Schwalbe, P. Tolias, M. P. Böhme, Z. A. Moldabekov, and J. Vorberger, Ab initio density response and local field factor of warm dense hydrogen, Matter Radiat. Extremes 9, 057401 (2024).
- T. Dornheim, Fermion sign problem in path integral Monte Carlo simulations: Quantum dots, ultracold atoms, and warm dense matter, Phys. Rev. E 100, 023307 (2019).
- M. Troyer and U. J. Wiese, Computational complexity and fundamental limitations to fermionic quantum Monte Carlo simulations, Phys. Rev. Lett. 94, 170201 (2005).
- B. Militzer, F. González-Cataldo, S. Zhang, K. P. Driver, and F. Soubiran, First-principles equation of state database for warm dense matter computation, Phys. Rev. E 103, 013203 (2021).
- J. McHardy, An introduction to the theory and use of SESAME equations of state, Tech. Rep., Los Alamos National Laboratory, Los Alamos, NM, 2018.
- A. B. Zylstra, O. A. Hurricane, D. A. Callahan, A. L. Kritcher, J. E. Ralph, H. F. Robey, J. S. Ross, C. V. Young, K. L. Baker, D. T. Casey, T. Döppner, L. Divol, M. Hohenberger, S. Le Pape, A. Pak, P. K. Patel, R. Tommasini, S. J. Ali, P. A. Amendt, L. J. Atherton et al., Burning plasma achieved in inertial fusion, Nature (London) 601, 542 (2022).
- A. L. Kritcher, C. V. Young, H. F. Robey, C. R. Weber, A. B. Zylstra, O. A. Hurricane, D. A. Callahan, J. E. Ralph, J. S. Ross, K. L. Baker, D. T. Casey, D. S. Clark, T. Döppner, L. Divol, M. Hohenberger, L. B. Hopkins, S. L. Pape, N. B. Meezan, A. Pak, P. K. Patel et al., Design of inertial fusion implosions reaching the burning plasma regime, Nat. Phys. 18, 251 (2022).
- M. M. Marinak, G. B. Zimmerman, T. Chapman, G. D. Kerbel, M. V. Patel, J. M. Koning, S. M. Sepke, B. Chang, C. R. Schroeder, J. A. Harte, D. S. Bailey, L. A. Taylor, S. H. Langer, M. A. Belyaev, D. S. Clark, J. Gaffney, B. A. Hammel, D. E. Hinkel, A. L. Kritcher, J. L. Milovich et al., How numerical simulations helped to achieve breakeven on the NIF, Phys. Plasmas 31, 070501 (2024).
- O. A. Hurricane, P. K. Patel, R. Betti, D. H. Froula, S. P. Regan, S. A. Slutz, M. R. Gomez, and M. A. Sweeney, Physics principles of inertial confinement fusion and U.S. program overview, Rev. Mod. Phys. 95, 025005 (2023).
- H. R. Griem, Principles of Plasma Spectroscopy, Cambridge Monographs on Plasma Physics (Cambridge University Press, Cambridge, UK, 1997).
- G. Ecker and W. Kröll, Lowering of the ionization energy for a plasma in thermodynamic equilibrium, Phys. Fluids 6, 62 (1963).
- J. C. Stewart and K. D. Stewart, Jr., Lowering of ionization potentials in plasmas, Astrophys. J. 144, 1203 (1966).
- O. Ciricosta, S. M. Vinko, H.-K. Chung, B.-I. Cho, C. R. D. Brown, T. Burian, J. Chalupský, K. Engelhorn, R. W. Falcone, C. Graves, V. Hájková, A. Higginbotham, L. Juha, J. Krzywinski, H. J. Lee, M. Messerschmidt, C. D. Murphy, Y. Ping, D. S. Rackstraw, A. Scherz et al., Direct measurements of the ionization potential depression in a dense plasma, Phys. Rev. Lett. 109, 065002 (2012).
- D. J. Hoarty, P. Allan, S. F. James, C. R. D. Brown, L. M. R. Hobbs, M. P. Hill, J. W. O. Harris, J. Morton, M. G. Brookes, R. Shepherd, J. Dunn, H. Chen, E. Von Marley, P. Beiersdorfer, H. K. Chung, R. W. Lee, G. Brown, and J. Emig, Observations of the effect of ionization-potential depression in hot dense plasma, Phys. Rev. Lett. 110, 265003 (2013).
- S. B. Hansen, E. C. Harding, P. F. Knapp, M. R. Gomez, T. Nagayama, and J. E. Bailey, Changes in the electronic structure of highly compressed iron revealed by x-ray fluorescence lines and absorption edges, High Energy Density Phys. 24, 39 (2017).
- S. X. Hu, D. T. Bishel, D. A. Chin, P. M. Nilson, V. V. Karasiev, I. E. Golovkin, M. Gu, S. B. Hansen, D. I. Mihaylov, N. R. Shaffer et al., Probing atomic physics at ultrahigh pressure using laser-driven implosions, Nat. Commun. 13, 6780 (2022).
- O. Ciricosta, S. M. Vinko, B. Barbrel, D. S. Rackstraw, T. R. Preston, T. Burian, J. Chalupský, B. I. Cho, H.-K. Chung, G. L. Dakovski, K. Engelhorn, V. Hájková, P. Heimann, M. Holmes, L. Juha, J. Krzywinski, R. W. Lee, S. Toleikis, J. J. Turner, U. Zastrau et al., Measurements of continuum lowering in solid-density plasmas created from elements and compounds, Nat. Commun. 7, 11713 (2016).
- C. A. Iglesias and P. A. Sterne, Fluctuations and the ionization potential in dense plasmas, High Energy Density Phys. 9, 103 (2013).
- C. A. Iglesias, A plea for a reexamination of ionization potential depression measurements, High Energy Density Phys. 12, 5 (2014).
- O. Ciricosta, S. M. Vinko, H.-K. Chung, C. Jackson, R. W. Lee, T. R. Preston, D. S. Rackstraw, and J. S. Wark, Detailed model for hot-dense aluminum plasmas generated by an x-ray free electron laser, Phys. Plasmas 23, 022707 (2016).
- T. Gawne, T. Campbell, A. Forte, P. Hollebon, G. Perez-Callejo, O. S. Humphries, O. Karnbach, M. F. Kasim, T. R. Preston, H. J. Lee, A. Miscampbell, Q. Y. van den Berg, B. Nagler, S. Ren, R. B. Royle, J. S. Wark, and S. M. Vinko, Investigating mechanisms of state localization in highly ionized dense plasmas, Phys. Rev. E 108, 035210 (2023).
- P. A. Sterne, S. B. Hansen, B. G. Wilson, and W. A. Isaacs, Equation of state, occupation probabilities and conductivities in the average atom purgatorio code, High Energy Density Phys. 3, 278 (2007), radiative Properties of Hot Dense Matter.
- V. V. Karasiev, S. X. Hu, N. R. Shaffer, and G. Miloshevsky, First-principles study of -shell iron and chromium opacity at stellar interior temperatures, Phys. Rev. E 106, 065202 (2022).
- T. Gawne, S. M. Vinko, and J. S. Wark, Quantifying ionization in hot dense plasmas, Phys. Rev. E 109, L023201 (2024).
- U. S. Whang, E. T. Arakawa, and T. A. Callcott, Optical properties of K between 4 and 10.7 eV and comparison with Na, Rb, and Cs, Phys. Rev. B 6, 2109 (1972).
- T. Kobayasi and M. Watabe, Remark on the conductivity sum rule for the optical absorptions of alkali metals, Solid State Commun. 13, 59 (1973).
- M. Bethkenhagen, B. B. L. Witte, M. Schörner, G. Röpke, T. Döppner, D. Kraus, S. H. Glenzer, P. A. Sterne, and R. Redmer, Carbon ionization at gigabar pressures: An ab initio perspective on astrophysical high-density plasmas, Phys. Rev. Res. 2, 023260 (2020).
- T. Döppner, M. Bethkenhagen, D. Kraus, P. Neumayer, D. A. Chapman, B. Bachmann, R. A. Baggott, M. P. Böhme, L. Divol, R. W. Falcone, L. B. Fletcher, O. L. Landen, M. J. MacDonald, A. M. Saunders, M. Schörner, P. A. Sterne, J. Vorberger, B. B. L. Witte, A. Yi, R. Redmer et al., Observing the onset of pressure-driven k-shell delocalization, Nature (London) 618, 270 (2023).
- M. N. Saha and A. Fowler, On a physical theory of stellar spectra, Proc. R. Soc. London, Ser. A 99, 135 (1921).
- M. Bonitz and L. Kordts, Ionization potential depression and Fermi barrier in warm dense matter—A first-principles approach, Contrib. Plasma Phys. e70001 (2025).
- S. M. Vinko, O. Ciricosta, and J. S. Wark, Density functional theory calculations of continuum lowering in strongly coupled plasmas, Nat. Commun. 5, 3533 (2014).
- C. E. Starrett, T. Q. Thelen, C. J. Fontes, and D. A. Rehn, Excited states in warm and hot dense matter, Phys. Rev. E 109, 035201 (2024).
- T. Q. Thelen, D. A. Rehn, C. J. Fontes, and C. E. Starrett, Predicting excitation energies in warm and hot dense matter, Phys. Rev. E 110, 015207 (2024).
- J. Zeng, A. Deng, C. Gao, Y. Hou, and J. Yuan, Extended chemical picture of ionization balance to extremely dense plasmas, Phys. Rev. E 111, 015211 (2025).
- D. Kraus, A. Ravasio, M. Gauthier, D. O. Gericke, J. Vorberger, S. Frydrych, J. Helfrich, L. B. Fletcher, G. Schaumann, B. Nagler, B. Barbrel, B. Bachmann, E. J. Gamboa, S. Göde, E. Granados, G. Gregori, H. J. Lee, P. Neumayer, W. Schumaker, T. Döppner et al., Nanosecond formation of diamond and lonsdaleite by shock compression of graphite, Nat. Commun. 7, 10970 (2016).
- D. Kraus, B. Bachmann, B. Barbrel, R. W. Falcone, L. B. Fletcher, S. Frydrych, E. J. Gamboa, M. Gauthier, D. O. Gericke, S. H. Glenzer, S. Göde, E. Granados, N. J. Hartley, J. Helfrich, H. J. Lee, B. Nagler, A. Ravasio, W. Schumaker, J. Vorberger, and T. Döppner, Characterizing the ionization potential depression in dense carbon plasmas with high-precision spectrally resolved x-ray scattering, Plasma Phys. Control Fusion 61, 014015 (2019).
- L. B. Fletcher, A. L. Kritcher, A. Pak, T. Ma, T. Döppner, C. Fortmann, L. Divol, O. S. Jones, O. L. Landen, H. A. Scott, J. Vorberger, D. A. Chapman, D. O. Gericke, B. A. Mattern, G. T. Seidler, G. Gregori, R. W. Falcone, and S. H. Glenzer, Observations of continuum depression in warm dense matter with x-ray Thomson scattering, Phys. Rev. Lett. 112, 145004 (2014).
- B. J. B. Crowley, Continuum lowering—A new perspective, High Energy Density Phys. 13, 84 (2014).
- M. F. Kasim, T. P. Galligan, J. Topp-Mugglestone, G. Gregori, and S. M. Vinko, Inverse problem instabilities in large-scale modeling of matter in extreme conditions, Phys. Plasmas 26, 112706 (2019).
- J. Vorberger, T. R. Preston, N. Medvedev, M. P. Böhme, Z. A. Moldabekov, D. Kraus, and T. Dornheim, Revealing non-equilibrium and relaxation in laser heated matter, Phys. Lett. A 499, 129362 (2024).
- T. Dornheim, M. P. Böhme, D. A. Chapman, D. Kraus, T. R. Preston, Z. A. Moldabekov, N. Schlünzen, A. Cangi, T. Döppner, and J. Vorberger, Imaginary-time correlation function thermometry: A new, high-accuracy and model-free temperature analysis technique for x-ray Thomson scattering data, Phys. Plasmas 30, 042707 (2023).
- H. M. Bellenbaum, B. Bachmann, D. Kraus, T. Gawne, M. P. Böhme, T. Döppner, L. B. Fletcher, M. J. MacDonald, Z. A. Moldabekov, T. R. Preston, J. Vorberger, and T. Dornheim, Toward model-free temperature diagnostics of warm dense matter from multiple scattering angles, Appl. Phys. Lett. 126, 044104 (2025).
- T. Dornheim, Z. Moldabekov, P. Tolias, M. Böhme, and J. Vorberger, Physical insights from imaginary-time density–density correlation functions, Matter Radiat. Extremes 8, 056601 (2023).
- T. Dornheim, Z. A. Moldabekov, K. Ramakrishna, P. Tolias, A. D. Baczewski, D. Kraus, T. R. Preston, D. A. Chapman, M. P. Böhme, T. Döppner, F. Graziani, M. Bonitz, A. Cangi, and J. Vorberger, Electronic density response of warm dense matter, Phys. Plasmas 30, 032705 (2023).
- J. Chihara, Difference in x-ray scattering between metallic and non-metallic liquids due to conduction electrons, J. Phys. F 17, 295 (1987).
- T. Dornheim, H. M. Bellenbaum, M. Bethkenhagen, S. B. Hansen, M. P. Böhme, T. Döppner, L. B. Fletcher, T. Gawne, D. O. Gericke, S. Hamel, D. Kraus, M. J. MacDonald, Z. A. Moldabekov, T. R. Preston, R. Redmer, M. Schörner, S. Schwalbe, P. Tolias, and J. Vorberger, Model-free rayleigh weight from x-ray Thomson scattering measurements, Phys. Plasmas 32, 052712 (2025).
- J. Vorberger and D. O. Gericke, Ab initio approach to model x-ray diffraction in warm dense matter, Phys. Rev. E 91, 033112 (2015).
- K. Wünsch, J. Vorberger, G. Gregori, and D. O. Gericke, X-ray scattering as a probe for warm dense mixtures and high-pressure miscibility, Europhys. Lett. 94, 25001 (2011).
- M. P. Böhme, L. B. Fletcher, T. Döppner, D. Kraus, A. D. Baczewski, T. R. Preston, M. J. MacDonald, F. R. Graziani, Z. A. Moldabekov, J. Vorberger, and T. Dornheim, Evidence of free-bound transitions in warm dense matter and their impact on equation-of-state measurements, arXiv:2306.17653.
- D. Kremp, M. Schlanges, and T. Bornath, Quantum Statistics of Nonideal Plasmas, Springer Series on Atomic, Optical, and Plasma Physics (Springer, Berlin, 2005).
- R. M. More, Electronic energy-levels in dense plasmas, J. Quant. Spectrosc. Radiat. Transfer 27, 345 (1982).
- D. Chandler and P. G. Wolynes, Exploiting the isomorphism between quantum theory and classical statistical mechanics of polyatomic fluids, J. Chem. Phys. 74, 4078 (1981).
- Y. Xiong and H. Xiong, On the thermodynamic properties of fictitious identical particles and the application to fermion sign problem, J. Chem. Phys. 157, 094112 (2022).
- M. Boninsegni, N. V. Prokofev, and B. V. Svistunov, Worm algorithm and diagrammatic Monte Carlo: A new approach to continuous-space path integral Monte Carlo simulations, Phys. Rev. E 74, 036701 (2006).
- M. Boninsegni, N. V. Prokofev, and B. V. Svistunov, Worm algorithm for continuous-space path integral Monte Carlo simulations, Phys. Rev. Lett. 96, 070601 (2006).
- T. Dornheim, M. Böhme, B. Militzer, and J. Vorberger, Ab initio path integral Monte Carlo approach to the momentum distribution of the uniform electron gas at finite temperature without fixed nodes, Phys. Rev. B 103, 205142 (2021).
- N. Metropolis, A. W. Rosenbluth, M. N. Rosenbluth, A. H. Teller, and E. Teller, Equation of state calculations by fast computing machines, J. Chem. Phys. 21, 1087 (1953).
- S. Groth, T. Dornheim, T. Sjostrom, F. D. Malone, W. M. C. Foulkes, and M. Bonitz, Ab initio exchange-correlation free energy of the uniform electron gas at warm dense matter conditions, Phys. Rev. Lett. 119, 135001 (2017).
- T. Dornheim, S. Groth, and M. Bonitz, The uniform electron gas at warm dense matter conditions, Phys. Rep. 744, 1 (2018).
- V. V. Karasiev, S. B. Trickey, and J. W. Dufty, Status of free-energy representations for the homogeneous electron gas, Phys. Rev. B 99, 195134 (2019).
- T. Dornheim, Z. A. Moldabekov, and J. Vorberger, Nonlinear density response from imaginary-time correlation functions: Ab initio path integral Monte Carlo simulations of the warm dense electron gas, J. Chem. Phys. 155, 054110 (2021).
- T. Dornheim, M. Böhme, and S. Schwalbe, ISHTAR—Imaginary-time stochastic high-performance tool for ab initio research, Zenodo (2024).
- M. Böhme, Z. A. Moldabekov, J. Vorberger, and T. Dornheim, Ab initio path integral Monte Carlo simulations of hydrogen snapshots at warm dense matter conditions, Phys. Rev. E 107, 015206 (2023).
- M. Böhme, Z. A. Moldabekov, J. Vorberger, and T. Dornheim, Static electronic density response of warm dense hydrogen: Ab initio path integral Monte Carlo simulations, Phys. Rev. Lett. 129, 066402 (2022).
- H. Bellenbaum, M. Böhme, M. Bonitz, T. Döppner, L. B. Fletcher, T. Gawne, D. Kraus, Z. Moldabekov, S. Schwalbe, J. Vorberger, and T. Dornheim, Data publication: Estimating ionization states and continuum lowering from ab initio path integral Monte Carlo simulations for warm dense hydrogen (Version 1) [Data set], Rodare (2025), http://doi.org/10.14278/rodare.3775.
- T. Dornheim, J. Vorberger, Z. A. Moldabekov, and M. Böhme, Analysing the dynamic structure of warm dense matter in the imaginary-time domain: Theoretical models and simulations, Philos. Trans. R. Soc. A 381, 20220217 (2023).
- T. Dornheim, T. Döppner, A. D. Baczewski, P. Tolias, M. P. Böhme, Z. A. Moldabekov, T. Gawne, D. Ranjan, D. A. Chapman, M. J. MacDonald, T. R. Preston, D. Kraus, and J. Vorberger, X-ray Thomson scattering absolute intensity from the f-sum rule in the imaginary-time domain, Sci. Rep. 14, 14377 (2024).
- D. A. Chapman, User guide for the multi-component scattering simulation (MCSS) code, Tech. rep., AWE, Aldermaston, Reading, UK, 2017.
- T. Dornheim, A. Cangi, K. Ramakrishna, M. Böhme, S. Tanaka, and J. Vorberger, Effective static approximation: A fast and reliable tool for warm-dense matter theory, Phys. Rev. Lett. 125, 235001 (2020).
- T. Dornheim, Z. A. Moldabekov, and P. Tolias, Analytical representation of the local field correction of the uniform electron gas within the effective static approximation, Phys. Rev. B 103, 165102 (2021).
- M. Schumacher, F. Smend, and I. Borchert, Incoherent scattering of gamma rays by inner-shell electrons, J. Phys. B 8, 1428 (1975), bF-DSF Formulation.
- G. Giuliani and G. Vignale, Quantum Theory of the Electron Liquid (Cambridge University Press, Cambridge, UK, 2008).
- E. Hückel, Zur Theorie der Elektrolyte, in Ergebnisse der exakten naturwissenschaften (Springer Berlin Heidelberg, Berlin, Heidelberg, 1924), pp. 199–276.
- S. Chiesa, D. M. Ceperley, R. M. Martin, and M. Holzmann, Finite-size error in many-body simulations with long-range interactions, Phys. Rev. Lett. 97, 076404 (2006).
- T. Dornheim, S. Groth, T. Sjostrom, F. D. Malone, W. M. C. Foulkes, and M. Bonitz, Ab initio quantum Monte Carlo simulation of the warm dense electron gas in the thermodynamic limit, Phys. Rev. Lett. 117, 156403 (2016).
- C. L. Epstein and J. Schotland, The bad truth about Laplace's transform, SIAM Rev. 50, 504 (2008).
- T. Chuna, N. Barnfield, T. Dornheim, M. P. Friedlander, and T. Hoheisel, Dual formulation of the maximum entropy method applied to analytic continuation of quantum Monte Carlo data, arXiv:2501.01869.
- L. G. Stanton, J. N. Glosli, and M. S. Murillo, Multiscale molecular dynamics model for heterogeneous charged systems, Phys. Rev. X 8, 021044 (2018).
- A. V. Filinov and M. Bonitz, Equation of state of partially ionized hydrogen and deuterium plasma revisited, Phys. Rev. E 108, 055212 (2023).
- S. M. Vinko, X-ray free-electron laser studies of dense plasmas, J. Plasma Phys. 81, 365810501 (2015).
- T. Dornheim, S. Groth, J. Vorberger, and M. Bonitz, Ab initio path integral Monte Carlo results for the dynamic structure factor of correlated electrons: From the electron liquid to warm dense matter, Phys. Rev. Lett. 121, 255001 (2018).
- M. Jarrell and J. E. Gubernatis, Bayesian inference and the analytic continuation of imaginary-time quantum Monte Carlo data, Phys. Rep. 269, 133 (1996).
- U. Zastrau, K. Appel, C. Baehtz, O. Baehr, L. Batchelor, A. Berghäuser, M. Banjafar, E. Brambrink, V. Cerantola, T. E. Cowan, H. Damker, S. Dietrich, S. Di Dio Cafiso, J. Dreyer, H.-O. Engel, T. Feldmann, S. Findeisen, M. Foese, D. Fulla-Marsa, S. Göde et al., The high energy density scientific instrument at the European XFEL, J. Synchrotron Radiat. 28, 1393 (2021).
- M. Rehwald, S. Assenbaum, C. Bernert, F.-E. Brack, M. Bussmann, T. E. Cowan, C. B. Curry, F. Fiuza, M. Garten, L. Gaus, M. Gauthier, S. Göde, I. Göthel, S. H. Glenzer, L. Huang, A. Huebl, J. B. Kim, T. Kluge, S. Kraft, F. Kroll et al., Ultra-short pulse laser acceleration of protons to 80 MeV from cryogenic hydrogen jets tailored to near-critical density, Nat. Commun. 14, 4009 (2023).