The Strong Enhancement of Electron-Impact Ionization Processes in Dense Plasma by Transient Spatial Localization
Recent experiments have observed much higher electron–ion collisional ionization cross sections and rates in dense plasmas than predicted by the current standard atomic collision theory, including the plasma screening effect. We suggest that the use of (distorted) plane waves for incident and scatte...
| Main Authors: | , , , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
MDPI AG
2022-05-01
|
| Series: | International Journal of Molecular Sciences |
| Subjects: | |
| Online Access: | https://www.mdpi.com/1422-0067/23/11/6033 |
| _version_ | 1797493146140016640 |
|---|---|
| author | Jiaolong Zeng Chen Ye Pengfei Liu Cheng Gao Yongjun Li Jianmin Yuan |
| author_facet | Jiaolong Zeng Chen Ye Pengfei Liu Cheng Gao Yongjun Li Jianmin Yuan |
| author_sort | Jiaolong Zeng |
| collection | DOAJ |
| description | Recent experiments have observed much higher electron–ion collisional ionization cross sections and rates in dense plasmas than predicted by the current standard atomic collision theory, including the plasma screening effect. We suggest that the use of (distorted) plane waves for incident and scattered electrons is not adequate to describe the dissipation that occurs during the ionization event. Random collisions with free electrons and ions in plasma cause electron matter waves to lose their phase, which results in the partial decoherence of incident and scattered electrons. Such a plasma-induced transient spatial localization of the continuum electron states significantly modifies the wave functions of continuum electrons, resulting in a strong enhancement of the electron–ion collisional ionization of ions in plasma compared to isolated ions. Here, we develop a theoretical formulation to calculate the differential and integral cross sections by incorporating the effects of plasma screening and transient spatial localization. The approach is then used to investigate the electron-impact ionization of ions in solid-density magnesium plasma, yielding results that are consistent with experiments. In dense plasma, the correlation of continuum electron energies is modified, and the integral cross sections and rates increase considerably. For the ionization of Mg<inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><msup><mrow></mrow><mrow><mn>9</mn><mo>+</mo></mrow></msup><mspace width="4pt"></mspace><mi>e</mi><mo>+</mo><mn>1</mn><msup><mi>s</mi><mn>2</mn></msup><mspace width="0.166667em"></mspace><mn>2</mn><mi>s</mi><msup><mspace width="0.166667em"></mspace><mrow><mn>2</mn><mspace width="-0.166667em"></mspace></mrow></msup><mi>S</mi><mo>→</mo><mn>1</mn><msup><mi>s</mi><mn>2</mn></msup><msup><mspace width="0.166667em"></mspace><mrow><mn>1</mn><mspace width="-0.166667em"></mspace></mrow></msup><mi>S</mi><mo>+</mo><mn>2</mn><mi>e</mi></mrow></semantics></math></inline-formula>, the ionization cross sections increase several-fold, and the rates increase by one order of magnitude. Our findings provide new insight into collisional ionization and three-body recombination and may aid investigations of the transport properties and nonequilibrium evolution of dense plasma. |
| first_indexed | 2024-03-10T01:15:49Z |
| format | Article |
| id | doaj.art-129c5c4d022048ca8662405954e90714 |
| institution | Directory Open Access Journal |
| issn | 1661-6596 1422-0067 |
| language | English |
| last_indexed | 2024-03-10T01:15:49Z |
| publishDate | 2022-05-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | International Journal of Molecular Sciences |
| spelling | doaj.art-129c5c4d022048ca8662405954e907142023-11-23T14:08:27ZengMDPI AGInternational Journal of Molecular Sciences1661-65961422-00672022-05-012311603310.3390/ijms23116033The Strong Enhancement of Electron-Impact Ionization Processes in Dense Plasma by Transient Spatial LocalizationJiaolong Zeng0Chen Ye1Pengfei Liu2Cheng Gao3Yongjun Li4Jianmin Yuan5College of Science, Zhejiang University of Technology, Hangzhou 310023, ChinaDepartment of Physics, College of Liberal Arts and Sciences, National University of Defense Technology, Changsha 410073, ChinaDepartment of Physics, College of Liberal Arts and Sciences, National University of Defense Technology, Changsha 410073, ChinaDepartment of Physics, College of Liberal Arts and Sciences, National University of Defense Technology, Changsha 410073, ChinaDepartment of Physics, College of Liberal Arts and Sciences, National University of Defense Technology, Changsha 410073, ChinaDepartment of Physics, College of Liberal Arts and Sciences, National University of Defense Technology, Changsha 410073, ChinaRecent experiments have observed much higher electron–ion collisional ionization cross sections and rates in dense plasmas than predicted by the current standard atomic collision theory, including the plasma screening effect. We suggest that the use of (distorted) plane waves for incident and scattered electrons is not adequate to describe the dissipation that occurs during the ionization event. Random collisions with free electrons and ions in plasma cause electron matter waves to lose their phase, which results in the partial decoherence of incident and scattered electrons. Such a plasma-induced transient spatial localization of the continuum electron states significantly modifies the wave functions of continuum electrons, resulting in a strong enhancement of the electron–ion collisional ionization of ions in plasma compared to isolated ions. Here, we develop a theoretical formulation to calculate the differential and integral cross sections by incorporating the effects of plasma screening and transient spatial localization. The approach is then used to investigate the electron-impact ionization of ions in solid-density magnesium plasma, yielding results that are consistent with experiments. In dense plasma, the correlation of continuum electron energies is modified, and the integral cross sections and rates increase considerably. For the ionization of Mg<inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><msup><mrow></mrow><mrow><mn>9</mn><mo>+</mo></mrow></msup><mspace width="4pt"></mspace><mi>e</mi><mo>+</mo><mn>1</mn><msup><mi>s</mi><mn>2</mn></msup><mspace width="0.166667em"></mspace><mn>2</mn><mi>s</mi><msup><mspace width="0.166667em"></mspace><mrow><mn>2</mn><mspace width="-0.166667em"></mspace></mrow></msup><mi>S</mi><mo>→</mo><mn>1</mn><msup><mi>s</mi><mn>2</mn></msup><msup><mspace width="0.166667em"></mspace><mrow><mn>1</mn><mspace width="-0.166667em"></mspace></mrow></msup><mi>S</mi><mo>+</mo><mn>2</mn><mi>e</mi></mrow></semantics></math></inline-formula>, the ionization cross sections increase several-fold, and the rates increase by one order of magnitude. Our findings provide new insight into collisional ionization and three-body recombination and may aid investigations of the transport properties and nonequilibrium evolution of dense plasma.https://www.mdpi.com/1422-0067/23/11/6033dense plasmatransient spatial localizationelectron scattering cross sectionselectron transport in gasesnon-thermal plasma |
| spellingShingle | Jiaolong Zeng Chen Ye Pengfei Liu Cheng Gao Yongjun Li Jianmin Yuan The Strong Enhancement of Electron-Impact Ionization Processes in Dense Plasma by Transient Spatial Localization International Journal of Molecular Sciences dense plasma transient spatial localization electron scattering cross sections electron transport in gases non-thermal plasma |
| title | The Strong Enhancement of Electron-Impact Ionization Processes in Dense Plasma by Transient Spatial Localization |
| title_full | The Strong Enhancement of Electron-Impact Ionization Processes in Dense Plasma by Transient Spatial Localization |
| title_fullStr | The Strong Enhancement of Electron-Impact Ionization Processes in Dense Plasma by Transient Spatial Localization |
| title_full_unstemmed | The Strong Enhancement of Electron-Impact Ionization Processes in Dense Plasma by Transient Spatial Localization |
| title_short | The Strong Enhancement of Electron-Impact Ionization Processes in Dense Plasma by Transient Spatial Localization |
| title_sort | strong enhancement of electron impact ionization processes in dense plasma by transient spatial localization |
| topic | dense plasma transient spatial localization electron scattering cross sections electron transport in gases non-thermal plasma |
| url | https://www.mdpi.com/1422-0067/23/11/6033 |
| work_keys_str_mv | AT jiaolongzeng thestrongenhancementofelectronimpactionizationprocessesindenseplasmabytransientspatiallocalization AT chenye thestrongenhancementofelectronimpactionizationprocessesindenseplasmabytransientspatiallocalization AT pengfeiliu thestrongenhancementofelectronimpactionizationprocessesindenseplasmabytransientspatiallocalization AT chenggao thestrongenhancementofelectronimpactionizationprocessesindenseplasmabytransientspatiallocalization AT yongjunli thestrongenhancementofelectronimpactionizationprocessesindenseplasmabytransientspatiallocalization AT jianminyuan thestrongenhancementofelectronimpactionizationprocessesindenseplasmabytransientspatiallocalization AT jiaolongzeng strongenhancementofelectronimpactionizationprocessesindenseplasmabytransientspatiallocalization AT chenye strongenhancementofelectronimpactionizationprocessesindenseplasmabytransientspatiallocalization AT pengfeiliu strongenhancementofelectronimpactionizationprocessesindenseplasmabytransientspatiallocalization AT chenggao strongenhancementofelectronimpactionizationprocessesindenseplasmabytransientspatiallocalization AT yongjunli strongenhancementofelectronimpactionizationprocessesindenseplasmabytransientspatiallocalization AT jianminyuan strongenhancementofelectronimpactionizationprocessesindenseplasmabytransientspatiallocalization |