Tailoring Curie temperature and magnetic anisotropy in ultrathin Pt/Co/Pt films

Journal Article · Sun May 15 04:00:00 EDT 2016 · AIP Advances

DOI:https://doi.org/10.1063/1.4944343· OSTI ID:22611760

Parakkat, Vineeth Mohanan; Ganesh, K. R.

The dependence of perpendicular magnetization and Curie temperature (T{sub c}) of Pt/Co/Pt thin films on the thicknesses of Pt seed (Pt{sub s}) and presence of Ta buffer layer has been investigated in this work. Pt and Co thicknesses were varied between 2 to 8 nm and 0.35 to 1.31 nm (across the spin reorientation transition thickness) respectively and the T{sub c} was measured using SQUID magnetometer. We have observed a systematic dependence of T{sub c} on the thickness of Pt{sub s}. For 8 nm thickness of Pt{sub s} the Co layer of 0.35 nm showed ferromagnetism with perpendicular anisotropy at room temperature. As the thickness of the Pt{sub s} was decreased to 2 nm, the T{sub c} went down below 250 K. XRD data indicated polycrystalline growth of Pt{sub s} on SiO{sub 2}. On the contrary Ta buffer layer promoted the growth of Pt(111). As a consequence Ta(5 nm)/Pt(3 nm)/Co(0.35 nm)/Pt(2 nm) had much higher T{sub c} (above 300 K) with perpendicular anisotropy when compared to the same stack without the Ta layer. Thus we could tune the ferromagnetic T{sub c} and anisotropy by varying the Pt{sub s} thickness and also by introducing Ta buffer layer. We attribute these observations to the micro-structural evolution of Pt{sub s} layer which hosts the Co layer.

• OSTI ID: 22611760
• Journal Information: AIP Advances, Journal Name: AIP Advances Journal Issue: 5 Vol. 6; ISSN AAIDBI; ISSN 2158-3226
• Country of Publication: United States
• Language: English

Related Subjects

75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
ANISOTROPY
BUFFERS
COBALT
COMPARATIVE EVALUATIONS
CURIE POINT
FERROMAGNETISM
LAYERS
MAGNETIC PROPERTIES
MAGNETIZATION
MAGNETOMETERS
PLATINUM
POLYCRYSTALS
SILICON OXIDES
SPIN
SQUID DEVICES
TEMPERATURE RANGE 0273-0400 K
THICKNESS
THIN FILMS
X-RAY DIFFRACTION