Spin-polarized electronic structure and magnetic properties of Ge 1−x TM x Te (TM=Mn, Fe)

Electronic structure and metal-insulator transition in crystalline magnetic phase-change material Ge1−xFexTe

“…These shifts are attributed to that the Fermi energy is shifted downward with respect to valence-band maximum (VBM) with increasing Fe concentrations, suggesting that Fe atoms give rise to shallow states near the Fermi energy. Previous calculations using density-functional theory indicated that Fe atoms result in shallow states near the Fermi energy in Ge 1Àx Fe x Te [10]. In addition, the area under the peak located between À1 and 6 eV increases with increasing Fe contents, which is attributed to increased contribution from Fe 3d orbitals [10,20].…”

“…Previous calculations using density-functional theory indicated that Fe atoms result in shallow states near the Fermi energy in Ge 1Àx Fe x Te [10]. In addition, the area under the peak located between À1 and 6 eV increases with increasing Fe contents, which is attributed to increased contribution from Fe 3d orbitals [10,20]. Thus the valence-band XPS analysis suggests the possibility of controlling the electronic structure and thereby carrier transport properties of Ge 1Àx Fe x Te films by the variation of Fe concentration.…”

“…In pure phasechange material GeTe, germanium vacancy leads to empty states at the top of the valence band, thus resulting in p-type conduction [8,9]. As for the TM-doped GeTe, previous calculations indicated that the transition metal dopant plays an important role in the electronic structure [9,10]. Thus, a detailed experimental investigation is required for an understanding of the electronic structure and charge transport in magnetic PCM Ge 1Àx Fe x Te.…”

First-Principles Study of the Structural, Electronic, Magnetic and Thermal Properties of the Cr Doped Ge6Mn2Te8 and Ge6Fe2Te8 Systems

“…Recently a large number of experimental studies related to the electronic structure [12][13][14], magnetism and magnetic transitions in several Ge-Te based alloys, such as Ge-Cr-Te, Ge-Mn-Te and Ge-Fe-Te have been reported [15][16][17]. In addition, there is a substantial amount of work on the DMS in general (please refer to Ref.…”

“…They studied the material systems theoretically using the ab initio calculations in order to explore new half-metallic ferromagnets based on the RS structure [10,17]. In recent times the calculated exchange interactions due to the carriers originating from these causes are sufficient to account for the observed ferromagnetism in the thin films of Ge 1−x Mn x Te, such as due to the Mn-Mn exchange interactions in the RS Ge 0.75 Mn 0.25 Te x Z 1−x alloys where Z represents the Sn-atoms or vacancies.…”