Pair-distribution functions of two-temperature two-mass systems: Comparison of molecular dynamics, classical-map hypernetted chain, quantum Monte Carlo, and Kohn-Sham calculations for dense hydrogen

Dharma‐wardana, M. W. C.; Murillo, Michael S.

doi:10.1103/physreve.77.026401

Cited by 34 publications

(12 citation statements)

References 25 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Important examples are metal-insulator transitions in transition metal oxides (Yoo et al, 2005;Rueff et al, 2005;Patterson et al, 2004;Mita et al, 2005Mita et al, , 2001Noguchi et al, 1996), (high T c ) superconductors (Nagamatsu et al, 2001;Bednorz and Müller, 1986) and protein folding (Anfinsen, 1972;Takai et al, 2008;Nicholls et al, 1991). More extreme examples are rapid heating of solids via strong laser fields (Gavnholt et al, 2009), dynamo effect in giant planets (Redmer et al, 2011), shock waves (Root et al, 2010;Militzer, 2006), warm dense matter (Kietzmann et al, 2008) and hot plasmas (Dharma-wardana and Perrot, 1982;Perrot and Dharma-wardana, 2000;Dharma-wardana and Murillo, 2008). Therefore the finite temperature framework is clearly of physical importance beyond our rather technical requirements.…”

Section: Resultsmentioning

confidence: 99%

One-body reduced density-matrix functional theory in finite basis sets at elevated temperatures

Giesbertz

Ruggenthaler

2019

Physics Reports

View full text Add to dashboard Cite

In this review we provide a rigorous and self-contained presentation of one-body reduced density-matrix (1RDM) functional theory. We do so for the case of a finite basis set, where density-functional theory (DFT) implicitly becomes a 1RDM functional theory. To avoid non-uniqueness issues we consider the case of fermionic and bosonic systems at elevated temperature and variable particle number, i.e, a grand-canonical ensemble. For the fermionic case the Fock space is finite-dimensional due to the Pauli principle and we can provide a rigorous 1RDM functional theory relatively straightforwardly. For the bosonic case, where arbitrarily many particles can occupy a single state, the Fock space is infinite-dimensional and mathematical subtleties (not every hermitian Hamiltonian is self-adjoint, expectation values can become infinite, and not every self-adjoint Hamiltonian has a Gibbs state) make it necessary to impose restrictions on the allowed Hamiltonians and external non-local potentials. For simple conditions on the interaction of the bosons a rigorous 1RDM functional theory can be established, where we exploit the fact that due to the finite one-particle space all 1RDMs are finite-dimensional. We also discuss the problems arising from 1RDM functional theory as well as DFT formulated for an infinite-dimensional one-particle space.

show abstract

Section: Resultsmentioning

confidence: 99%

One-body reduced density-matrix functional theory in finite basis sets at elevated temperatures

Giesbertz

Ruggenthaler

2019

Physics Reports

View full text Add to dashboard Cite

show abstract

“…V D). The validity of this approach has been verified by classical hypernetted-chain (CHNC) calculations [34,35], which indicates no changes of the structure factor S between k = 0.0348a −1 B and k = 0. On the other hand, the probed length is about 2000 times smaller than the hydrogen jet diameter D ∼ 18 μm, so we are far from the classical Mie scattering regime, which would require kD ∼ 1.…”

Section: Structure Factormentioning

confidence: 82%

Equilibration dynamics and conductivity of warm dense hydrogen

et al. 2014

View full text Add to dashboard Cite

We investigate subpicosecond dynamics of warm dense hydrogen at the XUV free-electron laser facility (FLASH) at DESY (Hamburg). Ultrafast impulsive electron heating is initiated by a ≤ 300-fs short x-ray burst of 92-eV photon energy. A second pulse probes the sample via x-ray scattering at jitter-free variable time delay. We show that the initial molecular structure dissociates within (0.9 ± 0.2) ps, allowing us to infer the energy transfer rate between electrons and ions. We evaluate Saha and Thomas-Fermi ionization models in radiation hydrodynamics simulations, predicting plasma parameters that are subsequently used to calculate the static structure factor. A conductivity model for partially ionized plasma is validated by two-temperature density-functional theory coupled to molecular dynamic simulations and agrees with the experimental data. Our results provide important insights and the needed experimental data on transport properties of dense plasmas.

show abstract

“…From these simulations, several simple plasmas properties can be immediately examined. In particular, we can calculate the explicit coupling between the ions and electrons through an interspecies coupling parameter Z Z e a T ( )( ) [88], species masses are m α and m γ , the ion-sphere radius is a ii =a i , and the electron-sphere radius is a a a n 3 4 ee ei e e 1 3 p = = = ( ) . We can additionally examine the screening strength κ=a i /λ e and degeneracy parameter Θ=T e /E F .…”

Section: Strong Electron-ion Couplingmentioning

confidence: 99%

“…Because electrons and ions are at different temperatures in most laboratory plasmas, it is important to develop an accurate two-temperature EOS. Although theoretical efforts have explored this topic over many years [88,[93][94][95][96], much less experimental work on this subject has been conducted. To understand the role that PIPPs could play in such experimental studies, we calculate final system pressures using MD simulations as the initial pressure of the gas phase is varied.…”

Section: Equation Of Statementioning

confidence: 99%

See 1 more Smart Citation

Controllable non-ideal plasmas from photoionized compressed gases

2018

View full text Add to dashboard Cite

Based on a suite of molecular dynamics simulations, we propose a strategy for producing non-ideal plasmas with controllable properties over a wide range of densities between those of ultracold neutral plasmas and those of solid-density plasmas. We simulated the formation of non-equilibrium plasmas from photoionized, cool gases that are spatially precorrelated through neutral-neutral interactions that are important at moderate-to-high pressures. A wide range of physical properties, including Coulomb collisional rates, partial pressures, screening strengths, continuum lowering, interspecies Coulomb coupling, electron degeneracy and ionization states, were characterized across more than an order of magnitude variation in the initial gas pressure. A wide range of plasma properties are also found to vary when the initial pressure of a precorrelated gas is varied. Thus, we propose that nonideal plasmas with tunable properties can be generated by photo-ionizing a dense, precorrelated gas. We find that the optimal initial density range for the gas is near a Kirkwood/Widom-Fisher line in the neutral-gas phase diagram. This strategy for generating non-ideal plasmas suggests experiments that have significant advantages over both ultracold and solid-density plasma experiments because the collisional, collective and recombination timescales can be tuned across many orders of magnitude, potentially allowing for a wider range of diagnostics. Moreover, the added costs of cooling ultracold plasmas and diagnosing dense matter with x-rays are eliminated. two-temperature variations (i.e., separate electron and ion temperatures). The desired method would allow for systematic control of plasma properties, including transport and relaxation, ionization-potential depression (IPD), the non-ideal multi-temperature equation of state (EOS), and screening involving strongly coupled electrons. Transport properties [43,44] and relaxation processes [45][46][47][48] are important to validate and model dense plasma experiments. The advent of XFEL [49-51] has renewed interest in IPD (a.k.a.'continuum lowering'), and dense plasma experiments have been used to validate different IPD models [52][53][54][55]. An accurate EOS is essential for examining plasma evolution on the hydrodynamic scale, such as the evolution of fluid instabilities in ICF experiments [56,57] or UCNP expansion into a vacuum [29]. Strongly coupled electrons, which are difficult to create at high densities because of degeneracy, have been of theoretical and experimental interest for several decades [21,22], including, more recently, for their role in the conductance of liquid-helium surfaces [23]. Finally, such an approach could also serve as a platform for measuring coupled electron-ion modes, which have been of recent interest in dense two-temperature plasmas [58]. In fact, isolated experiments at these intermediate densities have been performed successfully [59-61]; however, controllability and tunability of plasma properties were not the focus of those experiments. Here, we pr...

show abstract

Pair-distribution functions of two-temperature two-mass systems: Comparison of molecular dynamics, classical-map hypernetted chain, quantum Monte Carlo, and Kohn-Sham calculations for dense hydrogen

Cited by 34 publications

References 25 publications

One-body reduced density-matrix functional theory in finite basis sets at elevated temperatures

One-body reduced density-matrix functional theory in finite basis sets at elevated temperatures

Equilibration dynamics and conductivity of warm dense hydrogen

Controllable non-ideal plasmas from photoionized compressed gases

Contact Info

Product

Resources

About