Problem of phase transitions and thermodynamic stability in complex (dusty, colloid etc) plasmas

31st International Conference on Equations of State for Matter

Martynova, I.A.^1,2 ; Iosilevskiy, I.L.^1,2

Joint Institute for High Temperatures, Russian Academy of Sciences, Izhorskaya 13 Bldg 2, Moscow

125412, Russia^1

Moscow Institute of Physics and Technology, Institutskiy Pereulok 9, Dolgoprudny, Moscow Region

141700, Russia^2

关键词: Crystal types;    Debye systems;    Dusty plasmas;    First-order phase transitions;    Negative compressibilities;    Non-idealities;    Thermodynamic instability;    Thermodynamic variables;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/774/1/012173/pdf
DOI  :  10.1088/1742-6596/774/1/012173

来源: IOP

【 摘 要 】

Features of the first-order phase transitions in complex (dusty, colloid etc) plasma are under discussion. The basis for consideration is the well-known phase diagram of dusty plasma as a Debye system from Hamaguchi et al (1997 Phys. Rev. E 92 4671) in Γ-κ plane (Γ is a Coulomb non-ideality parameter, κ is a screening parameter). The initial Γ -κ phase diagram from Hamaguchi et al (1997 Phys. Rev. E 92 4671) is converted in standard thermodynamic variables in temperature-density planes. Here 2-component electroneutral systems of macro- and microions (+Z, -1) and (-Z, +1) are considered as thermodynamically equilibrium ensembles of classical Coulomb particles. An extensive area for negative compressibility of the system was revealed at the phase diagram in a fluid state of the initial Debye system when one considers the system as equilibrium two-component electroneutral mixture of macro- and microions (+Z, -1) (or (-Z, +1)) under equations of state from Hamaguchi et al (1997 Phys. Rev. E 92 4671) and Khrapak et al (2014 Phys. Rev. E 89 023102). This means thermodynamic instability of the simplified Debye system in this domain. Non-linear screening and an unavoidable existence of additional phase transitions of gas-liquid and gas-crystal type are proposed as hypothetical resolution of discussed thermodynamic instability problem.