Dynamic Property Of Electrons Coupled With Ions In Warm Or Hot Dense Hydrogen

The structure and property of warm or hot dense matter are the forefront and hot top-ics in high energy density physics,especially in astrophysics,planetary,inertial confine-ment fusion and design of materials under extreme conditions.The density of warm dense matter is near the solid density,and the temperature changes from a few electron volts to tens of electron volts（near the Fermi temperature）.Similarly,the density of hot dense matter is also close to the solid density,but the temperature is between several hundred electron volts and several thousand electron volts.With the development of experimen-tal technology,warm and hot dense matter can be produced in the laboratory,including NIF,X-ray free electron laser,and Hydrogen gun impact compression platforms.Due to the high temperature,the dynamics process is fast,and the traditional optical diagnosis method can not diagnose the state and the dynamics properties.At present,the X-ray Thompson Scattering techniques is validated to diagnose the state of warm or hot dense matter.In theory,the applicability of current theoretical models to be verified as the high density,which crosses the weak coupling and the strong coupling region.Further,the quantum effects are needed to be considered,as the degeneracy of electrons can not be neglected.In the process of ion-electron temperature relaxation,the current theoretical models are different from the experimental results,and it is a significant challenge in the study of the property of warm or hot dense matter.Firstly,we investigate the ion-electron temperature relaxation process in dense Hy-drogen with classical molecular dynamics.The ion temperature is fixed at 10 eV,while electron temperature changes from 20 eV to 200 eV.The electron number density is from1.0×10²²cm^-3to 1.0×10²⁴cm^-3,in which the electron is fully ionized.In order to solve the problem of Coulomb catastrophe in classical molecular dynamics,we introduce two potential,one is the HM potential,and the other is truncated Coulomb potential.At the same time,we investigate the effects of electron exchange to the relaxation process,and the results show that the exchange of electrons makes the relaxation process become slow,which is obvious only when the coupling parameterΓ>0.6.Next,we use electron force field method to investigate the electron quantum effect-s and coupling effects in temperature relaxation process.In essence,the electron force field method is the development of wave packet molecular dynamics,in which electrons are considered as Gaussian wave packets including translation and radial vibration,while ions are considered as charged points.The equation of movement is derived by intro-ducing the Gaussian wave packets into the time-dependent Schr?dinger equation,and it can describe well dissociation,ionization,excitation,and recombination.we need not to initially define which electrons are free and which are bound.The results show that the temperature relaxation rate is far less than current theoretical models and classical molec-ular dynamics,but is consistent with experimental results.Then we compare the struc-ture,diffusion coefficient,and mean free path between the electron force field method and classical molecular dynamics method,and find that electron degeneracy,non-localization,quantum scattering and the coupling with dense environment lead to the slow relaxation rate.Finally,we use electron force field method to calculate the transport properties of dense hydrogen with Green-Kubo formula,including electrical conductivity and thermal conductivity.For the hot dense matter,the electron wave packets will disperse,in which the temperature is above the Fermi temperature.We extend the electron force field method to control the disperse by fixing the radius of wave packet,and the results are well consis-tent with the current models.At the same time,we consider the effect of ion movement on the nature of electrical conductivity,and find the ion movement decreases the electrical conductivity.