Full Content is available to subscribers

Subscribe/Learn More  >
Proceedings Article

Spin angular momentum transfer in a current-perpendicular spin-valve nanomagnet

[+] Author Affiliations
Jonathan Z. Sun, Roger H. Koch

IBM Thomas J. Watson Research Ctr. (USA)

T. S. Kuan

SUNY/Albany (USA)

J. A. Katine

IBM Almaden Research Ctr. (USA)

Proc. SPIE 5359, Quantum Sensing and Nanophotonic Devices, 445 (July 6, 2004); doi:10.1117/12.521195
Text Size: A A A
From Conference Volume 5359

  • Quantum Sensing and Nanophotonic Devices
  • Manijeh Razeghi; Gail J. Brown
  • San Jose, CA, United States | January 26, 2004

abstract

Spin-angular momentum transfer (or spin-transfer for short) describes the angular momentum exchange between a spin-polarized current and a ferromagnetic conductor. When the conductor dimensions are reduced to around 100nm or below, the spin-angular momentum transfer effect becomes significant compared to the current-induced magnetic field. This paper describes some recent spin-transfer experimental findings in sub-100nm current-perpendicular spin-valve systems consisting of Co-Cu-Co nanopillars. The spin-transfer current is shown to cause a magnetic reversal of the thinner magnetic layer inside the nanopillar. The reversal is experimentally shown to reach sub-nanosecond speed. The effect of spin-transfer is best understood in terms of its modification to the effective Landau-Lifshiz-Gilbert damping coefficient, either increasing or decreasing its value depending on the direction and magnitude of the spin-polarized current. For sufficiently large spin-current, the net damping coefficient may change sign, resulting in amplification of magnetic precession, leading to a magnetic reversal. At finite temperatures, the effect of spin-transfer is to either increase or decrease the thermal agitation of the nanomagnet. A quantitative model is developed that adequately describes the finite temperature experimental observations of the dynamic spin-transfer effect.

© (2004) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

Topics

Magnetism
Citation

Jonathan Z. Sun ; T. S. Kuan ; J. A. Katine and Roger H. Koch
"Spin angular momentum transfer in a current-perpendicular spin-valve nanomagnet", Proc. SPIE 5359, Quantum Sensing and Nanophotonic Devices, 445 (July 6, 2004); doi:10.1117/12.521195; http://dx.doi.org/10.1117/12.521195


Access This Proceeding
Sign in or Create a personal account to Buy this proceeding ($15 for members, $18 for non-members).

Figures

Tables

NOTE:
Citing articles are presented as examples only. In non-demo SCM6 implementation, integration with CrossRef’s "Cited By" API will populate this tab (http://www.crossref.org/citedby.html).

Some tools below are only available to our subscribers or users with an online account.

Related Content

Customize your page view by dragging & repositioning the boxes below.

Related Book Chapters

Advertisement


  • Don't have an account?
  • Subscribe to the SPIE Digital Library
  • Create a FREE account to sign up for Digital Library content alerts and gain access to institutional subscriptions remotely.
Access This Proceeding
Sign in or Create a personal account to Buy this proceeding ($15 for members, $18 for non-members).
Access This Proceeding
Sign in or Create a personal account to Buy this article ($15 for members, $18 for non-members).
Access This Chapter

Access to SPIE eBooks is limited to subscribing institutions and is not available as part of a personal subscription. Print or electronic versions of individual SPIE books may be purchased via SPIE.org.