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

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

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.

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Y. Ishida, D. D. Sarma, K. Okazaki, J. Okabayashi, J. I. Hwang, H. Ott, A. Fujimori, G. A. Medvedkin, T. Ishibashi, K. Sato. 2003-04-11. In situ photoemission study of the room-temperature ferromagnet ZnGeP_2:Mn. https://doi.org/10.1103/physrevlett.91.107202

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