Half-metallic ferromagnetism and large negative magnetoresistance in the new lacunar spinel GaTi3VS8.
The lacunar spinel compounds GaTi(4-x)V(x)S(8) (0 < x < 4), consisting of Ti(4-x)V(x) tetrahedral clusters, were prepared and their structures were determined by powder X-ray diffraction. The electronic structures of GaTi(4-x)V(x)S(8) (x = 0, 1, 2, 3) were examined by density functional calculations, and the electrical resistivity and magnetic susceptibility of these compounds were measured. Our calculations predict that GaTi(3)VS(8) is a ferromagnetic half-metal, and this prediction was confirmed by magnetotransport experiments performed on polycrystalline samples of GaTi(3)VS(8). The latter reveal a large negative magnetoresistance (up to 22% at 2 K), which is consistent with the intergrain tunnelling magnetoresistance expected for powder samples of a ferromagnetic half-metal and indicates the presence of high spin polarization greater than 53% in GaTi(3)VS(8).
Dorolti
Eugen
E
Institut des Materiaux Jean Rouxel (IMN), Université de Nantes, CNRS, 2, rue de la Houssinière, BP 32229, 44322 Nantes Cedex 3, France.
Cario
Laurent
L
Corraze
Benoît
B
Janod
Etienne
E
Vaju
Cristian
C
Koo
Hyun-Joo
HJ
Kan
Erjun
E
Whangbo
Myung-Hwan
MH