Impact of the photoelectric threshold sensitivity on the work function determination—Revealing ultra-low work functions of caesiated surfaces

Bibliographic Details
Title: Impact of the photoelectric threshold sensitivity on the work function determination—Revealing ultra-low work functions of caesiated surfaces
Authors: A. Heiler, R. Friedl, U. Fantz
Source: AIP Advances, Vol 12, Iss 3, Pp 035339-035339-11 (2022)
Publisher Information: AIP Publishing LLC, 2022.
Publication Year: 2022
Collection: LCC:Physics
Subject Terms: Physics, QC1-999
More Details: The exploitation of the photoelectric effect is a prominent method for the in situ measurement of the absolute work function of a surface. In the case of metallic surfaces, the Fowler theory is routinely applied for fitting or extrapolating the measured photoelectric yield data to determine the work function value. However, for the reliable application of the Fowler method, attention must be paid to the experimental sensitivity to the photoelectric behavior close to the threshold, which is mainly determined by the signal-to-noise ratio for photocurrent detection and the available photon energies used for irradiation. This is illustrated by means of applying a photoelectric work function measurement system during a Cs coating process of a metal surface, where insufficiently low photon energies or an unfavorable noise level can lead to a severe overestimation of the work function of the order of 1 eV. By a sufficient enhancement of the photoelectric sensitivity, it is now unveiled that ultra-low surface work functions of 1.25 ± 0.10 eV can be generated via caesiation of metallic surfaces (here molybdenum and stainless steel) under vacuum conditions of 10−6–10−5 mbar, which is most probably the result of the formation of an oxidized Cs adlayer.
Document Type: article
File Description: electronic resource
Language: English
ISSN: 2158-3226
Relation: https://doaj.org/toc/2158-3226
DOI: 10.1063/5.0078380
Access URL: https://doaj.org/article/ec017fd4ae09480582be59ad58e76b22
Accession Number: edsdoj.017fd4ae09480582be59ad58e76b22
Database: Directory of Open Access Journals
More Details
ISSN:21583226
DOI:10.1063/5.0078380
Published in:AIP Advances
Language:English