Quantum Efficiency Enhancement in CsI/Metal Photocathodes

Kong, Lingmei; Joly, Alan G.; Droubay, Timothy C.; Hess, Wayne P.

doi:10.1016/j.cplett.2015.01.010

Title: Quantum Efficiency Enhancement in CsI/Metal Photocathodes

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Abstract

High quantum efficiency enhancement is found for hybrid metal-insulator photocathodes consisting of thin films of CsI deposited on Cu(100), Ag(100), Au(111) and Au films irradiated by 266 nm laser pulses. Low work functions (near or below 2 eV) are observed following ultraviolet laser activation. Work functions are reduced by roughly 3 eV from that of clean metal surfaces. We discuss various mechanisms of quantum efficiency enhancement for alkali halide/metal photocathode systems and conclude that the large change in work function, due to Cs accumulation of Cs metal at the metal-alkali halide interface, is the dominant mechanism for quantum efficiency enhancement

Authors:: Kong, Lingmei; Joly, Alan G.; Droubay, Timothy C.; Hess, Wayne P.

Publication Date:: Sun Feb 01 00:00:00 EST 2015

Research Org.:: Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

Sponsoring Org.:: USDOE

OSTI Identifier:: 1184928

Report Number(s):: PNNL-SA-107505

DOE Contract Number:: AC05-76RL01830

Resource Type:: Journal Article

Journal Name:: Chemical Physics Letters, 621:155-159

Additional Journal Information:: Journal Name: Chemical Physics Letters, 621:155-159

Country of Publication:: United States

Language:: English

Citation Formats


                    Kong, Lingmei, Joly, Alan G., Droubay, Timothy C., and Hess, Wayne P. Quantum Efficiency Enhancement in CsI/Metal Photocathodes.  United States: N. p., 2015. 
        Web.  doi:10.1016/j.cplett.2015.01.010.

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                    Kong, Lingmei, Joly, Alan G., Droubay, Timothy C., & Hess, Wayne P. Quantum Efficiency Enhancement in CsI/Metal Photocathodes.  United States.  https://doi.org/10.1016/j.cplett.2015.01.010

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                    Kong, Lingmei, Joly, Alan G., Droubay, Timothy C., and Hess, Wayne P. 2015.  
        "Quantum Efficiency Enhancement in CsI/Metal Photocathodes".  United States.  https://doi.org/10.1016/j.cplett.2015.01.010.

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@article{osti_1184928,

  title        = {Quantum Efficiency Enhancement in CsI/Metal Photocathodes},

  author       = {Kong, Lingmei and Joly, Alan G. and Droubay, Timothy C. and Hess, Wayne P.},

  abstractNote = {High quantum efficiency enhancement is found for hybrid metal-insulator photocathodes consisting of thin films of CsI deposited on Cu(100), Ag(100), Au(111) and Au films irradiated by 266 nm laser pulses. Low work functions (near or below 2 eV) are observed following ultraviolet laser activation. Work functions are reduced by roughly 3 eV from that of clean metal surfaces. We discuss various mechanisms of quantum efficiency enhancement for alkali halide/metal photocathode systems and conclude that the large change in work function, due to Cs accumulation of Cs metal at the metal-alkali halide interface, is the dominant mechanism for quantum efficiency enhancement},

  doi          = {10.1016/j.cplett.2015.01.010},

  url          = {https://www.osti.gov/biblio/1184928},
  journal      = {Chemical Physics Letters, 621:155-159},
number       = ,

  volume       = ,

  place        = {United States},

  year         = {Sun Feb 01 00:00:00 EST 2015},

  month        = {Sun Feb 01 00:00:00 EST 2015}

}

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