This paper develops a general approach to the derivation of the boundary conditions for hydrodynamic equations for charged and neutral plasma components. It includes both a well-known classical case for pure diffusion and considers the expressions for diffusion and drift together—for an absorbing (neutralizing) wall with partial reflection and the possible emission of plasma components. Some unclear and controversial terms found in the existing literature are clarified. Several examples of applications of the results, which illustrate the properties of boundary conditions for electrons and ions, are calculated and analyzed.

In this work, the Paschen curves and current–voltage characteristics of three large-area short glow discharge structures with grid and solid plate electrodes are studied. The study of the Paschen's curves reveals that Paschen's law is broken for all three investigated electrode structures. It is shown that the experimentally measured Paschen curves are well approximated with a modified Paschen's law. A comparison of the current–voltage characteristics of the short glow discharge in the three types of electrode structures reveals that the use of grid electrodes allows for the increase in the discharge current. The effects of the electrode gap, which were varied from 1 mm to 7 mm, on the Paschen curves and current–voltage characteristics of short glow discharges are also investigated.

The plasma sheath causes the spacecraft’s communication signal to attenuate dramatically during the re‐entry period, which seriously threatens the astronauts. However, valid experimental protocols have not been obtained hitherto. To realize the propagation of electromagnetic waves in negative permittivity background of the plasma sheath, alumina columns are embedded in the plasma background to form plasma photonic crystals, which can support the coupling of evanescent waves between the alumina columns. We experimentally demonstrate the realization of communication in blackout scenario by achieving a complete passing band in the plasma cutoff region. For high frequency communications in the plasma sheath, electromagnetic wave propagation based on topological edge states is also experimentally demonstrated. Furthermore, we realize a triply‐degenerate Dirac cone formed dynamically at the center of the Brillouin zone by modulating the electron density, where electromagnetic wave exhibits high transmittance and does not experience phase accumulation at the Dirac point. Our work thus not only provides an effective approach to overcome the communication blackout problem, but the design can also be served as a promising experimental platform to explore topological electromagnetic phenomena.

Plasma blackout, which contains ablative impurities, strongly attenuates the signal of the reentry spacecraft. Traditional methods focus on mitigating electron densities and impurities around the antenna, and metamaterial-based electromagnetic methods have yet to be proven experimentally. We simulate the plasma blackout problem using laboratory plasma supported by gas discharge technology. Alumina pillars are embedded in the plasma background to form plasma photonic crystals, while topological phase transitions are achieved by shrinking and expanding pillars within a unit cell. The topological edge states (TESs) that are insensitive to weak impurities in the transport path are verified theoretically and experimentally. We introduce the glide-reflection (GR) symmetry in the nontrivial lattices to obtain the gapless edge states, which are exclusively observed in the acoustic systems. Meanwhile, the Δω of the gapless TES increases with the electron densities, ensuring a wide communication bandwidth. Furthermore, the strong coupling of heterostructure with GR symmetry in plasma photonic crystals is elucidated. Our work not only provides a new approach to the blackout communication problem but can also serve as a nascent experimental platform to investigate topological electromagnetic phenomena.

The formation mechanisms of an inverse electron distribution function (EDF) in gas-discharge plasma are investigated. An approximate analytical model of an inverse EDF in an inhomogeneous electric field and the formation criteria are presented. It is shown that the regions of EDF inversion in classical glow discharges are located in the transition regions to the right and left of the positive column in areas with significant gradients of the electron density. An interesting feature of the EDF behavior in the vicinity of the second reversal point of the electric field is discovered in the numerical simulation results. At least one of the second-order partial derivatives in the solution of the Boltzmann kinetic equation for the isotropic part of the EDF has a discontinuity at this point.

A 1D plasma photonic crystal (PPC) is filled with plasmas and slab dielectrics in a large volume cylindrical glow discharge device. The parameters of the PPC are designed to meet the transmission condition of broadband microwave (1.5GHz-12GHz) according to the photonic crystal theory in which the thickness of the plasma is comparable to the wavelength. The transmission characteristics of broadband microwave in this plasma photonic crystal are demonstrated experimentally. The experiments show some unique characteristics of microwave in the PPCs, and the physical explanations for the phenomenon have been given based on the photonic crystal theory. And then, the features of the PPCs are compared to the corresponding photonic crystals (PCs) through both experiments and simulations. The results show that plasma slabs in PCs can change the band structure and influence the transmission of microwaves, which can be useful to the design of microwaves devices with PPCs.