INVESTIGADORES
RENTERIA Mario
congresos y reuniones científicas
Título:
Ab-Initio Study of Ferromagnetism Induced by Magnetic Impurities in Rutile TiO2.
Autor/es:
L.A. ERRICO; M. WEISSMANN; M. RENTERÍA.
Lugar:
Pucón
Reunión:
Conferencia; XI Latin American Congress of Surface Science and its Applications; 2003
Institución organizadora:
Universidad de Chile
Resumen:
Integrating spin
functionality into otherwise nonmagnetic materials has become a highly
desirable goal in the last years. In particular, dilute magnetic impurities in
semiconductors and oxides produce novel materials appealing for spintronics and
optoelectronics (see, e.g., refs. [1-2] and other references therein). Magnetic
dopants in nonmagnetic solids are assumed to couple with the electronic states
of the host, but remaining magnetically active. While most of the dilute
magnetic semiconductors have Curie temperatures much lower than room
temperature, this is not so for Co-doped rutile and anatase TiO2 and
rutile SnO2 [2], [3]. However, many questions remain regarding the
precise location of Co in the host lattice and the underlying microscopic
mechanism of long-range magnetic order.
In this contribution we
present a set of density-functional-theory-based calculations in the systems RxTi1-xO2
(R = Mn, Fe, Co, Ni). The calculations were performed with the WIEN97
implementation [4] of the full-potential linearized-augmented-plane-wave
(FP-LAPW) method, assuming that the magnetic impurities substitutionally
replace the Ti ions. The results are compared with previous calculations and
experiments.
This research was
partially supported by CONICET, Fundación Antorchas, ANPCyT (PICT 03-03727), Argentina, and TWAS, Italy.
References
[1] Z. Yang, G. Liu, and R.
Wu, Phys. Rev. B 67, R60402 (2003).
[2] J. Y. Kim, Phys. Rev.
Lett. 90, 17401 (2003).
[3] S. B. Ogale et al.,
Phys. Rev. Lett. 91, 77205 (2003).
[4] P.
Blaha, K. Schwarz, P. Dufek, and J. Luitz, Wien97, (K. Schwarz, Technische
Universtität Wien, Austria, 1999), ISBN
3-9501031-0-4.