Room temperature positive magnetoresistance

[rejinisaac1]

I've achieved positive magnetoresistance (MR) in CNT composite thin films with a small percentage of Fe in it. Fe injects spin polarized electrons into CNT. But +ve MR means that resistance is increasing with magnetic field. But due to injection of spin polarized electrons the current has to increase and hence the resistance has to go down. Is my view right? If yes, what could be the factor that is leading to the increase in resistance? experiments were done in a range of 0 to 1.1 tesla. Please help me

 

[amghaderi]

Could magnetostriction of the Fe in your CNTs be affecting the resistivity?

 

[rejinisaac1]

magnetostriction in Fe is negligible...MR is increasing with increase in CNT

 

[saaskis]

You achieved positive MR only after Fe was added, so it's not a weak antilocalization effect in carbon?

EDIT: Probably not due to room temperature...

 

[rejinisaac1]

positive MR was achieved with Fe. no MR was observed in case of just CNTs. positive MR was observed when CNT concentration was fixed and Fe increased and also when Fe concentration was fixed and CNT increased. what could be the reason??