Sub-threshold ultrafast one-photon photoemission from a Cu(111) photocathode
Single-photon photoemission of electrons for incident photon energies below the surface work function is reported for a single-crystal Cu(111) photocathode. Spectral characterization of the quantum efficiency and mean transverse energy of the emitted electrons is shown to be consistent with emission...
| Main Authors: | , , |
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| Format: | Article |
| Language: | English |
| Published: |
AIP Publishing LLC
2022-10-01
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| Series: | AIP Advances |
| Online Access: | http://dx.doi.org/10.1063/5.0099779 |
| _version_ | 1798023513668321280 |
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| author | L. A. Angeloni I.-J. Shan W. Andreas Schroeder |
| author_facet | L. A. Angeloni I.-J. Shan W. Andreas Schroeder |
| author_sort | L. A. Angeloni |
| collection | DOAJ |
| description | Single-photon photoemission of electrons for incident photon energies below the surface work function is reported for a single-crystal Cu(111) photocathode. Spectral characterization of the quantum efficiency and mean transverse energy of the emitted electrons is shown to be consistent with emission from a thermalized hot electron distribution photoexcited on sub-picosecond time scales into an upper conduction band at the L-point of the Brillouin zone of copper. To our knowledge, this is the first time that such excited-state thermionic emission has been observed from a planar metal photocathode, and then from a commonly used photocathode material. The results, therefore, indicate the potential importance of such band structure dependent sub-threshold photoemission mechanisms on the performance of photocathodes employed for the generation of short electron pulses using sub-picosecond laser pulses. Consequently, the combined experimental and theoretical work presented in this paper contributes to solid-state photocathode-based research aimed at our understanding and selection (or discovery) of high brightness photo-electron sources required for many electron-based diffraction, imaging, and accelerator applications. |
| first_indexed | 2024-04-11T17:47:31Z |
| format | Article |
| id | doaj.art-40579c583430460ca6671b1c0447d087 |
| institution | Directory Open Access Journal |
| issn | 2158-3226 |
| language | English |
| last_indexed | 2024-04-11T17:47:31Z |
| publishDate | 2022-10-01 |
| publisher | AIP Publishing LLC |
| record_format | Article |
| series | AIP Advances |
| spelling | doaj.art-40579c583430460ca6671b1c0447d0872022-12-22T04:11:14ZengAIP Publishing LLCAIP Advances2158-32262022-10-011210105129105129-910.1063/5.0099779Sub-threshold ultrafast one-photon photoemission from a Cu(111) photocathodeL. A. Angeloni0I.-J. Shan1W. Andreas Schroeder2Department of Physics (m/c 273), University of Illinois at Chicago, 845 W. Taylor Street, Chicago, Illinois 60607, USADepartment of Physics (m/c 273), University of Illinois at Chicago, 845 W. Taylor Street, Chicago, Illinois 60607, USADepartment of Physics (m/c 273), University of Illinois at Chicago, 845 W. Taylor Street, Chicago, Illinois 60607, USASingle-photon photoemission of electrons for incident photon energies below the surface work function is reported for a single-crystal Cu(111) photocathode. Spectral characterization of the quantum efficiency and mean transverse energy of the emitted electrons is shown to be consistent with emission from a thermalized hot electron distribution photoexcited on sub-picosecond time scales into an upper conduction band at the L-point of the Brillouin zone of copper. To our knowledge, this is the first time that such excited-state thermionic emission has been observed from a planar metal photocathode, and then from a commonly used photocathode material. The results, therefore, indicate the potential importance of such band structure dependent sub-threshold photoemission mechanisms on the performance of photocathodes employed for the generation of short electron pulses using sub-picosecond laser pulses. Consequently, the combined experimental and theoretical work presented in this paper contributes to solid-state photocathode-based research aimed at our understanding and selection (or discovery) of high brightness photo-electron sources required for many electron-based diffraction, imaging, and accelerator applications.http://dx.doi.org/10.1063/5.0099779 |
| spellingShingle | L. A. Angeloni I.-J. Shan W. Andreas Schroeder Sub-threshold ultrafast one-photon photoemission from a Cu(111) photocathode AIP Advances |
| title | Sub-threshold ultrafast one-photon photoemission from a Cu(111) photocathode |
| title_full | Sub-threshold ultrafast one-photon photoemission from a Cu(111) photocathode |
| title_fullStr | Sub-threshold ultrafast one-photon photoemission from a Cu(111) photocathode |
| title_full_unstemmed | Sub-threshold ultrafast one-photon photoemission from a Cu(111) photocathode |
| title_short | Sub-threshold ultrafast one-photon photoemission from a Cu(111) photocathode |
| title_sort | sub threshold ultrafast one photon photoemission from a cu 111 photocathode |
| url | http://dx.doi.org/10.1063/5.0099779 |
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