Vortex Induced by DC Current in a Circular Magnetic Spin Valve Nanopillar

Author

Chang, L.J. ; Lin, Pang ; Lee, Shang Fan

Author_Institution

Inst. of Phys., Taipei, Taiwan

Volume

48

Issue

4

fYear

2012

fDate

4/1/2012 12:00:00 AM

Firstpage

1297

Lastpage

1300

Abstract

We investigate the characteristic of vortex states induced by a dc current in trilayer circular magnetic nanopillars experimentally. Our samples are designed such that both the soft and hard layers can contain a magnetic vortex and the interlayer is thick enough such that only dipolar interaction is important. The relative chiralities between the two layers´ vortex configurations as functions of external field and current are studied with various diameters. We also perform micromagnetic simulation on the magnetization reversals to compare with the magnetoresistance (MR) curves measured at low current and with current induced magnetization states. The current induced magnetization behaviors due to the spin transfer torque effect and the additional Oersted field are clearly identified on the resistance behavior.

Keywords

chirality; magnetic fields; magnetisation reversal; magnetoresistance; spin valves; DC current; Oersted field; circular magnetic spin valve nanopillar; current induced magnetization states; dipolar interaction; external field functions; hard layers; magnetic vortex state; magnetization reversals; magnetoresistance curves; micromagnetic simulation; relative chirality; soft layers; spin transfer torque effect; trilayer circular magnetic nanopillars; vortex configurations; Magnetic cores; Magnetization; Resistance; Saturation magnetization; Scanning electron microscopy; Switches; Torque; Magnetic vortex state; spin transfer torque;

fLanguage

English

Journal_Title

Magnetics, IEEE Transactions on

Publisher

ieee

ISSN

0018-9464

Type

jour

DOI

10.1109/TMAG.2011.2173670

Filename

6172350