S. X. Hu et al., Phys. Rev. Lett. 104, 235003 (2010).
 S. X. Hu et al., Phys. Rev. B 84, 224109 (2011).
 S. X. Hu, T. R. Boehly, and L. A. Collins, Phys. Rev. E 89, 063104 (2014).
 S. X. Hu et al., Phys. Rev. E 92, 043104 (2015).
 Y. H. Ding and S. X. Hu, Phys. Plasmas 24, 062702 (2017).
 S. X. Hu et al., Phys. Rev. B 94, 094109 (2016).
 S. X. Hu et al., Phys. Rev. E 95, 043210 (2016).
First-Principles Opacity Table (FPOT) of Warm Dense Matter
Opacity/emissivity determines how much x-ray radiation is absorbed/emitted in systems. Once materials are highly compressed and heated, atoms and ions in such HED systems can no longer be viewed as individual entities. The surrounding plasma environment will significantly alter the opacity and emissivity in such HED systems. For ICF and HED applications, we have been using the ab initio quantum-molecular-dynamics (QMD) method, based on density-functional theory, to study the first-principles optical properties of materials under high pressures. These FPOT studies have covered DT , C , and CH  so far. Implementing FPOT in our ICF/HED hydrocodes also redefines reliable 1-D target designs. We are currently developing the QMD method, by writing a real-space discrete-variable-representation, all-electron, TD-DFT code for studying the optical properties of mid-/high-Z materials. Some examples of our recent results show that traditional continuum-lowering models can be wrong for strongly coupled and degenerate plasmas:
Ab initio Studies of Transport Properties in HED Plasmas
Transport properties, including thermal/electrical conductivity, diffusivity, viscosity, and stopping-power, are important quantities to know for ICF and HED experiment simulations. These properties essentially determine both energy and mass transport in such systems. For the past few years, we have been using quantum molecular-dynamics (QMD) method, based on density-functional theory, to study the first-principles transport properties of materials under high pressures. These studies have covered the thermal conductivity and ionization of DT  and CH  and their effects on ICF simulations . Currently, we are developing a TD-DFT code for extending our calculations of the transport properties of HED plasmas to high-temperature regimes. Some examples of our recent results show that traditional thermal-conduction models can be wrong for strongly coupled and degenerate plasmas:
 S. X. Hu et al., Phys. Rev. E 89, 043105 (2014).
 S. X. Hu et al., Phys. Plasmas 23, 042704 (2016).
 S. X. Hu et al., Phys. Plasmas 22, 056304 (2015).
Developing Accurate Density-Functional-Theory (DFT) Methods
The accuracy and efficiency of the modern DFT method really depends on the advancement in finding the best exchange-correlation functionals. To that end, we have put effort on developing an accurate presentation for the free-energy functional over a wide range of state conditions . In addition, improving the orbital-free DFT simulations for high-temperature plasmas is one of our current focuses, through introducing temperature-dependent xc-functional . We wish to continue this works to accurately simulate warm dense matter.
 V. V. Karasiev, J. W. Dufty, and S. B. Trickey, Phys. Rev. Lett. 120, 076401 (2018).
 V. V. Karasiev et al., Phys. Rev. Lett. 112, 076403 (2014).
Combing QMD-CMD for Simulations of HED dynamics
In collaboration with Profs. Chuang Ren and Niaz Abdolrahim from ME at the University of Rochester, we are planning to combine the QMD method with classical molecular-dynamics (CMD) simulations to tackle dynamical problems in HED sciences. Basically, QMD can give the ion–ion interaction potentials in an HED system, while the CMD method can use such first-principles potentials to simulate the dynamics of large systems consisting of thousands or even up to millions of atoms. The goals are to answer many fundamental questions, such as:
- How quick phase-transition happens under dynamic loading?
- What are the transient states behind shocks?
- How fast thermal equilibrium among species occurs in a shocked mixture?