In situ photoemission study of the room-temperature ferromagnet ZnGeP_2:Mn

Ishida, Y.; Sarma, D. D.; Okazaki, K.; Okabayashi, J.; Hwang, J. I.; Ott, H.; Fujimori, A.; Medvedkin, G. A.; Ishibashi, T.; Sato, K.

In situ photoemission study of the room-temperature ferromagnet ZnGeP_2:Mn

Authors

Description

The chemical states of the ZnGeP$_{2}$:Mn interface, which shows ferromagnetism above room-temperature, has been studied by photoemission spectroscopy. Mn deposition on the ZnGeP$_2$ substrate heated to 400$^{\circ}$C induced Mn substitution for Zn and then the formation of metallic Mn-Ge-P compounds. Depth profile studies have shown that Mn 3$d$ electrons changed their character from itinerant to localized along the depth, and in the deep region, dilute divalent Mn species ($\textless$ 5 % Mn) was observed with a coexisting metallic Fermi edge of non-Mn 3$d$ character. The possibility of hole doping through Mn substitution for Ge and/or Zn vacancy is discussed.
4 pages, 5 figures