We determine the work functions of the iron arsenic compounds AFe2As2 (A=Ca,Ba,Cs) using photoemission spectroscopy to be 2.7 eV for CaFe2As2, 1.8 eV for BaFe2As2, and 1.3 eV for CsFe2As2. The work functions of these 122 iron-based superconductors track those of the elementary metal A but are substantially smaller. The most likely explanation of this observation is that the cleaving surface exposes only half an A-layer. The low work function and good photoemission cross section of BaFe2As2 and CsFe2As2 enable photoemission even from a common white LED light.
All Science Journal Classification (ASJC) codes
- Materials Science(all)
- Physics and Astronomy (miscellaneous)