Spin-transfer in an open ferromagnetic layer: from negative damping to effective temperature

Details Spin-transfer in an open ferromagnetic layer: from negative damping to effective temperature Spin-transfer in an open ferromagnetic layer: from negative damping to effective temperature

2006-10-10

arxiv.org/abs/cond-mat/0610264v1

Physics

Condensed Matter

Materials Science

65 pages, 10 figures

Scientific paper

Spin-transfer is a typical spintronics effect that allows a ferromagnetic layer to be switched by spin-injection. Most of the experimental results about spin transfer are described on the basis of the Landau-Lifshitz-Gilbert equation of the magnetization, in which additional current-dependent damping factors are added, and can be positive or negative. The origin of the damping can be investigated further by performing stochastic experiments, like one shot relaxation experiments under spin-injection in the activation regime of the magnetization. In this regime, the N\'eel-Brown activation law is observed which leads to the introduction of a current-dependent effective temperature. In order to justify the introduction of these counterintuitive parameters (effective temperature and negative damping), a detailed thermokinetic analysis of the different sub-systems involved is performed. We propose a thermokinetic description of the different forms of energy exchanged between the electric and the ferromagnetic sub-systems at a Normal/Ferromagnetic junction. The corresponding Fokker Planck equations, including relaxations, are derived. The damping coefficients are studied in terms of Onsager-Casimir transport coefficients, with the help of the reciprocity relations. The effective temperature is deduced in the activation regime.

Affiliated with

Also associated with

No associations

Rating

Spin-transfer in an open ferromagnetic layer: from negative damping to effective temperature does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Spin-transfer in an open ferromagnetic layer: from negative damping to effective temperature, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Spin-transfer in an open ferromagnetic layer: from negative damping to effective temperature will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-437409