Shock Physics in Warm Dense Matter--a quantum hydrodynamics perspective

Warm dense matter (WDM)–an exotic, highly compressed state of matter between solid and plasma phases is of high current interest, in particular for astrophysics and inertial confinement fusion. For the latter, in particular the propagation of compression shocks is crucial. The main unknown in the shock propagation in WDM is the behavior of the electrons since they are governed by correlations, quantum and spin effects that need to be accounted for simultaneously. Here we describe the shock dynamics of the warm dense electron gas using a quantum hydrodynamic model. From the numerical hydrodynamic simulations we observe that the quantum Bohm pressure induces shear force which weakens the formation and strength of the shock.
In addition, the Bohm pressure induces an electron density response which takes the form of oscillations. This is confirmed by the theoretical analysis of the early stage of the shock formation. Our theoretical and numerical analysis allows us to identify characteristic dimensionless shock propagation parameters at which the effect of the Bohm force is important.