Nanocomposites and nanomaterials
Angular Dependence of Magnetoresistance of filled with iron Carbon Nanotubes
 Shpylka D.O. 1, Ovsiienko I.V. 1, Marinin O.D. 1, Len T.A. 1, 
Matzui L.Yu. 1, Prylutskyy Yu.I.2, Mirzoiev I.G.3, Berkutov I. B.3,4, Ritter U.5
 Taras Shevchenko National University of Kyiv, Department of Physics1and Biophysics2, 64/13 Volodymyrska st., 01601, Kyiv, Ukraine
3Verkin Institute for Low Temperature Physics and Engineering of the NAS of Ukraine, 47 Avenue of Science, 61103 , Kharkiv, Ukraine 
4Department of Physics, North Carolina State University, Raleigh, NC 27695, USA
5Technical University of Ilmenau, 25 Weimarer Str., 98693 Ilmenau, Germany E-mail: denys8600@ukr.net 

The work presents the results of investigations of magnetoresistance of filled with iron MWCNTs at different mutual orientation between the direction of the magnetic field and the direction of current through MWCNTs specimen. The MWCNTs with different iron concentration have been obtained by CVD method in tube furnace using benzene as carbon source material and ferrocene as iron source material and catalyst. For magnetoresistance measurements MWCNTs bulk specimens have been prepared by cold compacting without binder. The resistance has been measured in the temperature interval from 4.2 K to 293 K and in the magnetic fields up to 5 T. 
Figure presents the field dependences of magnetoresistance for filled MWCNTs with 2% mass (a) and 5% mass of iron at mutual orientation between the direction of the magnetic field and current 300 and 900 (inset). 
a	 b	It is found that the magnetoresistance of filled MWCNTs is a combination of giant magnetoresistance and anisotropic magnetoresistance, moreover, the relative contribution of each mechanism is determined by the concentration of the modifying metallic phase.	
Fig. R/R(B) for MWCNTs with 2% mass (a) and 5% mass of iron, =300 and  = 900 (inset)