Defect Dependent Polarized Spin Current in Co Doped ZnO Thin Films
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  • Defect Dependent Polarized Spin Current in Co Doped ZnO Thin Films

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Speaker: Dr. Musa Mutlu Can, Sabanci University, Istanbul

Title:
  "Defect Dependent Polarized Spin Current in Co Doped ZnO Thin Films"

Date/Time: 
Nov 30 Wednesday at 14.40

Location:
  FASS G022

Abstract:

The ferromagnetism, originated from polarized spins, in oxide diluted magnetic semiconductors (oxide-DMSs) were constructed on theories which point out the strong exchange coupling in between 2p levels of oxygen and d shells of transition metals [1-3] and in between the shallow impurity bands of defects and host 3d bands [4]. Accordingly, the carrier mediated ferromagnetism was effected from the types of 3d cations [5], local point defects [6,7] and carrier concentrations [8].Consequently, the formed shallow energy levels, originated from transition metals, n or p type doping and point defects, were identified as the main parameter leading magnetization in oxide- DMSs [1-7]. This study was based on magneto resistivity measurements that finds out the magnetic formation in Co and W doped ZnO thin films with a specific amount of defects. The results were reported based on the findings of longitudinal and transverse magneto electrical resistivity changes in the temperature range from 2K up to 300K under the magnetic field interval of ±90 kOe. The relation between the polarized spins and positive magneto resistivity was revealed under observations of mediated s-d and p-d exchange coupling. 

[1] T. Dietl, H. Ohno, F. Matsukura, J. Cibert, D. Ferrand, Scien., 287 (2000) 1019-1021
[2] J. M. D. Coey, M. Venkatesan, C. B. Fitzgerald, Natur. Mater. 4 (2005)173-179
[3] T. Fukumura, Y. Yamada, H. Toyosaki, T. Hasegawa, H. Koinuma, M. Kawasaki, Appl. Surf. Scien. 223 (2004) 62-67
[4] J. M. D. Coey, Sol. Stat. Scien. 7 (2005) 660-667
[5] D. Karmakar, S. K. Mandal, R. M. Kadam, P. L. Paulose, A. K. Rajarajan, T. K. Nath, A. K. Das, I. Dasgupta, G. P. Das, Phys. Rev. B, 75 (2007) 144404
[6] J. M. D. Coey, M. Venkatesan, C. B. Fitzgerald, Natur. Mater., Vol.4 (Feb 2005), 173-179
[7] X. J. Liu, C. Song, F. Zeng, F. Pan, Thin Solid Film, 516 (2008) 8757-8761
[8] K. R. Kittilstved, N. S. Norberg, D. R. Gamelin, Phys. Rev. Lett., 94 (2005), 147209



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