Enhanced quantum efficiency from hybrid cesium halide/copper photocathodes

Journal Article · Mon Apr 28 00:00:00 EDT 2014 · Applied Physics Letters

DOI:https://doi.org/10.1063/1.4874339· OSTI ID:22267737

Kong, Lingmei; Joly, Alan G.; Droubay, Timothy C.; Gong, Yu

The quantum efficiency (QE) of Cu is found to increase dramatically when coated by a CsI film and then irradiated by a UV laser. Over three orders of magnitude quantum efficiency enhancement at 266 nm is observed in CsI/Cu(100), indicating potential application in future photocathode devices. Upon laser irradiation, a large work function reduction to a value less than 2 eV is also observed, significantly greater than for similarly treated CsBr/Cu(100). The initial QE enhancement, prior to laser irradiation, is attributed to interface interaction and the intrinsic properties of the Cs halide film. Further QE enhancement following activation is attributed to formation of inter-band states and Cs metal accumulation at the interface induced by laser irradiation.

• OSTI ID: 22267737
• Journal Information: Applied Physics Letters, Vol. 104, Issue 17; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA); ISSN 0003-6951
• Country of Publication: United States
• Language: English

Related Subjects

71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
CESIUM BROMIDES
COPPER
LASER RADIATION
LASERS
PHOTOCATHODES
QUANTUM EFFICIENCY
WORK FUNCTIONS