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.
| Original language | English |
|---|---|
| Pages (from-to) | 1683-1686 |
| Number of pages | 4 |
| Journal | Ieee Transactions on Magnetics |
| Volume | 46 |
| Issue number | 6 |
| DOIs | |
| Publication status | Published - Jun 2010 |
Keywords
- \$hboxLa\_0.67hboxSr\_0.33hboxMnO\_3\$
- \$hbox\{La\}\_\{0.67\}hbox\{Sr\}\_\{0.33\}hbox\{MnO\}\_\{3\}\$
- Charge carriers
- cobalt
- Cobalt-doped \$hbox\{TiO\}\_\{2\}\$
- Cobalt-doped \$hboxTiO\_2\$
- conduction bands
- ELECTRODES
- ferromagnetic materials
- impurity states
- junction resistance
- La0.67Sr0.33MnO3-SrTiO3-TiO2:Co-Co
- lanthanum compounds
- MAGNETIC MATERIALS
- Magnetic semiconductor
- magnetic semiconductor electrodes
- magnetic semiconductors
- magnetic thin films
- Magnetic tunneling
- magnetic tunnel junction
- Magnetic tunnel junctions
- magnetoelectronics
- metallic impurity band conduction
- Mine
- negative tunnel magnetoresistance
- paramagnetic insulator
- paramagnetic materials
- pulsed laser deposition
- room-temperature ferromagnetism
- Semiconductor impurities
- semiconductor thin films
- spin polarised transport
- Spin-polarized tunneling
- Spintronics
- Strontium
- strontium compounds
- temperature 293 K to 298 K
- titanium compounds
- Tunneling magnetoresistance
- tunnelling magnetoresistance
- ultrathin interfacial layer