An investigation of the dynamics of vortices driven by spin-momentum transfer in magnetic tunnel junction nanopillars containing a vortex in the hard ferromagnetic pinned layer (PL) and a vortex in the soft ferromagnetic free layer (FL) is presented. This dual vortex configuration is interesting because the handedness of the vortex in the PL can be set so that the SMT is either assisted or opposed by the torque due to the Amperean magnetic field produced by the current passing through the nanopillar. It is shown that the handedness of the vortex in the PL controls the dynamics of the nanopillar device. Micromagnetic simulations of the three-dimensional nanopillar structures were performed as a function of PL vortex handedness, spin polarization , and nanopillar dimensions. Generally, for positive , it is found that when the PL vortex is set counter-clockwise (CCW), the FL vortex shows a well-defined switching behavior, where the handedness of the final vortex state in the FL is dependent on the current direction through the nanopillar, and the switching current is decreased as is increased. In devices where the PL is magnetized clockwise (CW), the FL magnetization dynamics show a more complicated dependence on . The CW magnetized PL nanopillars show high-current Amperean field-induced vortex switching at low , chaotic oscillation at intermediate , and well-defined low-current switching at high . For negative , the CCW and CW PL results invert.
Skip Nav Destination
Article navigation
1 April 2008
Proceedings of the 52nd Annual Conference on Magnetism and Magnetic Materials
5-9 November 2007
Tampa, Florida (USA)
Research Article|
Magnetism and Magnetic Materials|
April 02 2008
Effect of vortex handedness on spin momentum torque dynamics in dual-vortex ferromagnetic nanopillar structures
J. G. Deak
J. G. Deak
a)
NVE Corporation
, 11409 Valley View Road, Eden Prairie, Minnesota 55344, USA
Search for other works by this author on:
a)
Electronic mail: [email protected].
J. Appl. Phys. 103, 07A505 (2008)
Article history
Received:
September 14 2007
Accepted:
November 20 2007
Citation
J. G. Deak; Effect of vortex handedness on spin momentum torque dynamics in dual-vortex ferromagnetic nanopillar structures. J. Appl. Phys. 1 April 2008; 103 (7): 07A505. https://doi.org/10.1063/1.2838016
Download citation file:
Pay-Per-View Access
$40.00
Sign In
You could not be signed in. Please check your credentials and make sure you have an active account and try again.
Citing articles via
A step-by-step guide to perform x-ray photoelectron spectroscopy
Grzegorz Greczynski, Lars Hultman
Piezoelectric thin films and their applications in MEMS: A review
Jinpeng Liu, Hua Tan, et al.
Tutorial: Simulating modern magnetic material systems in mumax3
Jonas J. Joos, Pedram Bassirian, et al.
Related Content
Current-sweep-rate dependence of spin-torque driven dynamics in magnetic nanopillars
J. Appl. Phys. (February 2009)
Low frequency magnetization excitations in magnetic nanopillars induced by a dc spin-polarized current
J. Appl. Phys. (February 2009)
Spin-wave analysis of uniaxial nanopillar devices
J. Appl. Phys. (February 2009)
Current-induced magnetization dynamics in Co ∕ Cu ∕ Co nanopillars
J. Appl. Phys. (February 2008)
Current pulse induced toggle switching of dual-vortex magnetization in Ni80Fe20/Cu/Co nanopillar element
J. Appl. Phys. (October 2012)