ELFT HÍRADÓ

[Deák László <deak AT rmki.kfki.hu>]

Az RMKI Magfizikai Főosztályának anyagtudományi szemináriuma:


Prof. Eva Majková
 (Institute of Physics, Slovak Academy of Sciences, Bratislava)

"Correlation between structure and magnetic properties of CIMS pseudo spin
 valves"


Időpont:
           2007. június 27. (szerda), 14.00

Helyszín:  KFKI RMKI,
           III. épület, 2. emelet, tanácsterem
           (1121 Bp. Konkoly Thege M. út 29-33.)

Kivonat:

"The expanding field of spintronics calls for better understanding the 
correlations between microstructure including interface characteristics 
and magnetic properties of the multilayer stack in the nanoscale. The 
present work focuses on fabrication and characterization of pseudo spin 
valve structures important in future devices based on current switching 
magnetization phenomena. Special attention is directed to the 
characterization of interfaces and influence of Néel coupling.

The spin valve structures with Co/Au/Co active GMR region were prepared on 
Si substrate by UHV e-beam evaporation technique. For a comprehensive 
characterization of the multilayer stack the X-ray reflectivity and 
reciprocal space mapping were applied. By simulation of the experimental 
data the individual layer thickness, effective interface roughness, the 
geometrical interface roughness and its correlation properties parallel 
and perpendicular with respect to the interface were obtained. The study 
is completed by the inspection of the structure inside the layers using 
the X-ray diffraction. For simulation of the reciprocal space maps the 
DWBA approximation was used. Magnetization curves of prepared samples were 
measured by magneto-optical Kerr effect.

The effect of bottom Au electrode on the morphology of buried spin valve 
interfaces was shown from reciprocal space maps of diffusely scattered X-rays. 
The impact of interfaces morphology on the magnetic properties especially 
on the increase of spin valve coercivity was measured and simulated 
within the frame of Néel magnetostatic coupling  model based on the 
parameters from the X-ray diffuse scattering data. The presented x-ray 
mapping of the reciprocal space of spin valve structures is a non 
destructive approach suitable for a rapid statistical characterization of 
the interlayer properties which is able to reveal the origin of the Neel 
magnetostatic coupling."

Minden érdeklődőt szeretettel várunk!


                                      Deák László