Photoemission yield study of semimagnetic semiconductor Hg1−xFexSe crystals

Photoemission yield spectroscopy (PYS) was used to investigate HgSe and Hg0.88Fe0.12Se crystal surface freshly cleaved in a UHV chamber at a pressure of about 10−9 Torr. The spectral photoemission yield curves were measured in the vacuum-ultraviolet range (4 < hv < 11 eV). The experimental results show that the contribution of the Fe3d6 electrons to the electronic structure of the valence band leads to a shift of the work function from 4.30 to 4.15 eV. This contribution appears as an additional shoulder on the edge of the spectral photoemission yield curve. The interaction of the ambient atmosphere with the surfaces of freshly cleaved Hg1−xFexSe (x = 0.0, 0.12) crystals causes a decrease of the ionization energy Ei and the work function W.