Conditions for efficient spin injection from a ferromagnetic metal into a semiconductor

Physical Review B - Condensed Matter and Materials Physics

Volumn 64, Issue 18, 2001, Pages

  Fert, A ^a   Jaffres H ^a  

^a CNRS   (France)

Author keywords

[No Author keywords available]

Indexed keywords

FERROMAGNETIC MATERIAL;

ACCELERATION; ARTICLE; CALCULATION; CONDUCTANCE; MOLECULAR MODEL; SEMICONDUCTOR; THICKNESS;

EID: 0035509039     PISSN: 10980121     EISSN: 1550235X     Source Type: Journal    
DOI: 10.1103/PhysRevB.64.184420     Document Type: Article

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20. The resistivity and spin diffusion length (SDL) data we refer to in Sec. II to estimate (formula presented) and (formula presented) have been obtained at low temperature (LT) where most CPP-GMR experiments have been performed. Some CPP-GMR measurements have also been performed as a function of temperature on multilayered nanowires. The resistivity increases and the SDL decreases as a function of T, so that their product r changes only weakly, by 11% between LT and RT in Co for example (Ref. 20). This is also consistent with Eq. (14) and the Yafet mechanism of spin relaxation in which (formula presented) is temperature independent. The weak temperature dependence of (formula presented) (or (formula presented) justifies the use of LT data at any temperature.
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