Structural and magneto-transport characterization of Co_2Cr_xFe_(1-x)Al Heusler alloy films

Abstract

We investigate the structure and magneto-transport properties of thin films of the Co_2Cr_xFe_(1-x)Al full-Heusler compound, which is predicted to be a half-metal by first-principles theoretical calculations. Thin films are deposited by magnetron sputtering at room temperature on various substrates in order to tune the growth from polycrystalline on thermally oxidized Si substrates to highly textured and even epitaxial on MgO(001) substrates, respectively. Our Heusler films are magnetically very soft and ferromagnetic with Curie temperatures up to 630 K. The total magnetic moment is reduced compared to the theoretical bulk value, but still comparable to values reported for films grown at elevated temperature. Polycrystalline Heusler films combined with MgO barriers are incorporated into magnetic tunnel junctions and yield 37% magnetoresistance at room temperature.

References in corpus (5)

• Slater-Pauling Behavior of the Half-Ferromagnetic Full-Heusler Alloys
• Basic obstacle for electrical spin-injection from a ferromagnetic metal into a diffusive semiconductor
• Origin and Properties of the Gap in the Half-Ferromagnetic Heusler Alloys
• Appearance of Half-Metallicity in the Quaternary Heusler Alloys
• Magnetotransport in Single Crystal Half-Heusler Compounds

Cited by in corpus (3)

• Influence of mixing the low-valent transition metal atoms (Y,Y${}^{\ast }$=Cr,Mn,Fe) on the properties of the quaternary Co${}_2$[Y${}_{1-x}$Y${}_x^{\ast }$]Z (Z=Al,Ga,Si,Ge,Sn) Heusler compounds
• Engineering the electronic, magnetic and gap-related properties of the quinternary half-metallic Heusler alloys
• Large inverse tunneling magnetoresistance in Co${}_2$Cr${}_{0.6}$Fe${}_{0.4}$Al/MgO/CoFe magnetic tunnel junctions