Magnetic and electronic transport properties of Mn-doped Ge films have been studied as a function of Mn content. The films exhibit a long-range ferromagnetic behavior and a Mn dilution-dependent Curie temperature TC . Resistivity shows an insulator-like character with two distinct activation energies below about 80 K, while the Hall coefficient evidences a strong contribution from the anomalous Hall effect, in a p-type material. At a characteristic temperature TR, resistivity experiences a sudden reduction and the Hall coefficient reverses its sign from positive to negative. Moreover, around TR, any residual remanence and coercivity disappear. The transport and magnetic results are deeply related and can be qualitatively explained by a percolation model based on bound magnetic polarons due to localized holes in the GeMn alloy lattice.

Magnetic and transport polaron percolation in diluted GeMn films.

PINTO, Nicola;MURRI, Roberto Vittorio;
2006-01-01

Abstract

Magnetic and electronic transport properties of Mn-doped Ge films have been studied as a function of Mn content. The films exhibit a long-range ferromagnetic behavior and a Mn dilution-dependent Curie temperature TC . Resistivity shows an insulator-like character with two distinct activation energies below about 80 K, while the Hall coefficient evidences a strong contribution from the anomalous Hall effect, in a p-type material. At a characteristic temperature TR, resistivity experiences a sudden reduction and the Hall coefficient reverses its sign from positive to negative. Moreover, around TR, any residual remanence and coercivity disappear. The transport and magnetic results are deeply related and can be qualitatively explained by a percolation model based on bound magnetic polarons due to localized holes in the GeMn alloy lattice.
File in questo prodotto:
Non ci sono file associati a questo prodotto.

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/11581/203136
 Attenzione

Attenzione! I dati visualizzati non sono stati sottoposti a validazione da parte dell'ateneo

Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus 25
  • ???jsp.display-item.citation.isi??? 27
social impact