DocumentCode :
1498584
Title :
Magnetic Tunnel Junctions With 
Magnetic Semiconductor Electrodes
Author :
Lee, Y.J. ; Kumar, A. ; Marún, I. J Vera ; de Jong, M.P. ; Jansen, R.
Author_Institution :
MESA+ Inst. for Nanotechnol., Univ. of Twente, Enschede, Netherlands
Volume :
46
Issue :
6
fYear :
2010
fDate :
6/1/2010 12:00:00 AM
Firstpage :
1683
Lastpage :
1686
Abstract :
Spin-polarized tunneling is investigated in magnetic tunnel junctions containing an ultrathin interfacial layer of Co:TiO2 magnetic semiconductor. The Co:TiO2 layers (0 to 1 nm thick) are inserted at the SrTiO3/Co interface in La0.67Sr0.33MnO3/SrTiO3/Co tunnel junctions. For all junctions we find a negative tunnel magnetoresistance, which decreases upon the insertion of Co:TiO2, while the junction resistance increases strongly. This suggests that the ultrathin Co:TiO2 is a paramagnetic insulator that acts as an additional tunnel barrier, in contrast to thick (180 nm) layers grown under comparable conditions, which exhibit metallic impurity band conduction and room-temperature ferromagnetism.
Keywords :
cobalt; conduction bands; ferromagnetic materials; impurity states; lanthanum compounds; magnetic semiconductors; magnetic thin films; paramagnetic materials; semiconductor thin films; spin polarised transport; strontium compounds; titanium compounds; tunnelling magnetoresistance; La0.67Sr0.33MnO3-SrTiO3-TiO2:Co-Co; junction resistance; magnetic semiconductor electrodes; magnetic tunnel junctions; metallic impurity band conduction; negative tunnel magnetoresistance; paramagnetic insulator; room-temperature ferromagnetism; spin-polarized tunneling; temperature 293 K to 298 K; ultrathin interfacial layer; Charge carriers; Electrodes; Magnetic materials; Magnetic semiconductors; Magnetic tunneling; Magnetoelectronics; Pulsed laser deposition; Semiconductor impurities; Strontium; Tunneling magnetoresistance; $hbox{La}_{0.67}hbox{Sr}_{0.33}hbox{MnO}_{3}$ $hbox{TiO}_{2}$ ; magnetic semiconductor; magnetic tunnel junction; spintronics;
fLanguage :
English
Journal_Title :
Magnetics, IEEE Transactions on
Publisher :
ieee
ISSN :
0018-9464
Type :
jour
DOI :
10.1109/TMAG.2010.2046019
Filename :
5467477
Link To Document :
