We investigated postannealing temperature dependence of the structural and magnetic properties of Co2Ti0.5Mn0.5Al and Co2Ti0.5Mn0.5Si films. It was observed that the Co2Ti0.5Mn0.5Al film formed an ordered L2 1 structure and an ordered B2 structure after postannealing at above 873 K and below 773 K, respectively. The Co2Ti0.5Mn 0.5Si film deposited with substrate heating at above 473 K formed an ordered L21 structure. The obtained magnetoresistance ratio for a junction using an L21 ordered Co2Ti0.5Mn 0.5Si electrode was 12.5 at room temperature (RT). The estimated spin polarization of the Co2Ti0.5Mn0.5Si film was 0.14 at RT. The magnetoresistance ratios of a junction using a B2 ordered Co2Ti0.5Mn0.5Al electrode were 65.8 at RT and 128.4% at 7 K. The estimated spin polarizations of the Co2Ti 0.5Mn0.5Al film were 0.56 at RT and 0.78 at 7 K.
ASJC Scopus subject areas
- Physics and Astronomy(all)