Transport and magnetic properties of Mn2VAl: Search for half-metallicity

Polycrystalline Mn2VAl samples with the ordered L2(1) structure were examin ed by X-ray diffraction, magnetisation and resistivity measurements. The ma gneto moment at 5 K is 1.94 mu (B)/f.u. and the residual resistivity is 13 x 10(-8) Omega m, with little temperature dependence below 60 K. The low ma gnetoresistance (<0.1% at 1 T at 77 K) measured on polycrystalline samples or pressed powders makes it difficult to attribute a half-metallic characte r to Mn2VAl, as had been proposed on the basis of band structure calculatio n. (C) 2001 Published by Elsevier Science Ltd.