Transition from ultrafast laser photo-electron emission to space-charge-limited current in a 1D gap
A one-dimensional (1D) model has been constructed to study the transition of the time-dependent ultrafast laser photo-electron emission from a flat metallic surface to the space-charge-limited (SCL) current, including the effect of non-equilibrium laser heating on metals at the ultrafast time scale....
| Main Authors: | , |
|---|---|
| Other Authors: | |
| Format: | Journal Article |
| Language: | English |
| Published: |
2014
|
| Subjects: | |
| Online Access: | https://hdl.handle.net/10356/103814 http://hdl.handle.net/10220/19280 |
| _version_ | 1826120334859829248 |
|---|---|
| author | Liu, Yangjie Ang, L. K. |
| author2 | School of Electrical and Electronic Engineering |
| author_facet | School of Electrical and Electronic Engineering Liu, Yangjie Ang, L. K. |
| author_sort | Liu, Yangjie |
| collection | NTU |
| description | A one-dimensional (1D) model has been constructed to study the transition of the time-dependent ultrafast laser photo-electron emission from a flat metallic surface to the space-charge-limited (SCL) current, including the effect of non-equilibrium laser heating on metals at the ultrafast time scale. At high laser field, it is found that the space charge (SC) effect cannot be ignored and the SCL current emission is reached at a lower value predicted by a short-pulse SCL current model that has assumed a time-independent emission process. The threshold of the laser field to reach the SCL regime is determined over a wide range of operating parameters. The calculated results agree well with particle-in-cell simulation results. It is found that the SC effect is more important for materials with lower work function like tungsten (4.4 eV) as compared with gold (5.4 eV). However, for a flat surface, both materials will reach the SC limited regime at sufficient high laser field such as >5 GV m−1 with a laser pulse length of 10 s to 100 fs. |
| first_indexed | 2024-10-01T05:14:48Z |
| format | Journal Article |
| id | ntu-10356/103814 |
| institution | Nanyang Technological University |
| language | English |
| last_indexed | 2024-10-01T05:14:48Z |
| publishDate | 2014 |
| record_format | dspace |
| spelling | ntu-10356/1038142020-03-07T14:02:43Z Transition from ultrafast laser photo-electron emission to space-charge-limited current in a 1D gap Liu, Yangjie Ang, L. K. School of Electrical and Electronic Engineering DRNTU::Engineering::Electrical and electronic engineering A one-dimensional (1D) model has been constructed to study the transition of the time-dependent ultrafast laser photo-electron emission from a flat metallic surface to the space-charge-limited (SCL) current, including the effect of non-equilibrium laser heating on metals at the ultrafast time scale. At high laser field, it is found that the space charge (SC) effect cannot be ignored and the SCL current emission is reached at a lower value predicted by a short-pulse SCL current model that has assumed a time-independent emission process. The threshold of the laser field to reach the SCL regime is determined over a wide range of operating parameters. The calculated results agree well with particle-in-cell simulation results. It is found that the SC effect is more important for materials with lower work function like tungsten (4.4 eV) as compared with gold (5.4 eV). However, for a flat surface, both materials will reach the SC limited regime at sufficient high laser field such as >5 GV m−1 with a laser pulse length of 10 s to 100 fs. Accepted version 2014-04-30T08:02:52Z 2019-12-06T21:20:53Z 2014-04-30T08:02:52Z 2019-12-06T21:20:53Z 2014 2014 Journal Article Liu, Y., & Ang, L. K. (2014). Transition from ultrafast laser photo-electron emission to space-charge-limited current in a 1D gap. Journal of Physics D: Applied Physics, 47(12), 125502-. 0022-3727 https://hdl.handle.net/10356/103814 http://hdl.handle.net/10220/19280 10.1088/0022-3727/47/12/125502 en Journal of physics D : applied physics © 2014 IOP Publishing. This is the author created version of a work that has been peer reviewed and accepted for publication by Journal of Physics D: Applied Physics, IOP Publishing. It incorporates referee’s comments but changes resulting from the publishing process, such as copyediting, structural formatting, may not be reflected in this document. The published version is available at: [http://dx.doi.org/10.1088/0022-3727/47/12/125502]. application/pdf |
| spellingShingle | DRNTU::Engineering::Electrical and electronic engineering Liu, Yangjie Ang, L. K. Transition from ultrafast laser photo-electron emission to space-charge-limited current in a 1D gap |
| title | Transition from ultrafast laser photo-electron emission to space-charge-limited current in a 1D gap |
| title_full | Transition from ultrafast laser photo-electron emission to space-charge-limited current in a 1D gap |
| title_fullStr | Transition from ultrafast laser photo-electron emission to space-charge-limited current in a 1D gap |
| title_full_unstemmed | Transition from ultrafast laser photo-electron emission to space-charge-limited current in a 1D gap |
| title_short | Transition from ultrafast laser photo-electron emission to space-charge-limited current in a 1D gap |
| title_sort | transition from ultrafast laser photo electron emission to space charge limited current in a 1d gap |
| topic | DRNTU::Engineering::Electrical and electronic engineering |
| url | https://hdl.handle.net/10356/103814 http://hdl.handle.net/10220/19280 |
| work_keys_str_mv | AT liuyangjie transitionfromultrafastlaserphotoelectronemissiontospacechargelimitedcurrentina1dgap AT anglk transitionfromultrafastlaserphotoelectronemissiontospacechargelimitedcurrentina1dgap |