Pure spin currents generation in magnetic tunnel junctions by means of adiabatic quantum pumping
Dipartimento di Fisica “E.R. Caianiello", Università degli Studi di Salerno, C.N.I.S.M. Unità di Salerno, via S. Allende, 84081 Baronissi (SA), Italy
Corresponding author: a email@example.com
Revised: 19 January 2006
Published online: 5 May 2006
We study the spin polarized currents generation in a magnetic (ferromagnetic/ferromagnetic) tunnel junction by means of adiabatic quantum pumping. Using a scattering matrix approach, it is shown that a pure spin current can be pumped from one ferromagnetic lead into the adjacent one by adiabatic modulation of the magnetization and the height of the barrier at the interface in absence of external bias voltage. We numerically study the characteristic features of the pure spin current and discuss its behavior for realistic values of the parameters. We show that the generated pure spin current is robust with respect to the variation of the magnetization strength, a very important feature for a realistic device, and that the proposed device can operate close to the optimal pumping regime. An experimental realization of a pure spin current injector is also discussed.
PACS: 72.25.Ba – Spin polarized transport in metals / 05.60.Gg – Quantum transport / 85.75.-d – Magnetoelectronics; spintronics: devices exploiting spin polarized transport or integrated magnetic fields
© EDP Sciences, Società Italiana di Fisica, Springer-Verlag, 2006