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Circular Magnetic Elements: Ground States, Reversal and Dipolar Interactions

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Book cover Low-Dimensional Systems: Theory, Preparation, and Some Applications

Part of the book series: NATO Science Series ((NAII,volume 91))

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Abstract

The continuous reduction of the system sizes of magnetic materials into the nanometer regime has kept magnetism an attractive field of research for the past 15 years. New phenomena have been put into evidence, when the system size becomes comparable to typical magnetic or electronic length scales [1–3]. Besides being conceptually attractive to the physicist, these phenomena promise the development of new devices, called spinelectronic devices [4, 5]. Spin-electronics refers to the fact that in ferromagnets the conduction electrons can be distinguished depending on whether their spin is aligned parallel or antiparallel to the magnetization. Via spin dependent scattering, the electron spin orientation can then be used to control the electronic signal. For example, in spin-valve [5–7] and tunnel junction [8, 9] devices, two ferromagnetic layers are separated by a nonmagnetic (metallic or insulating) spacer layer. The resistance across this multilayer stack is higher when the magnetization in the two layers is aligned antiparallel as compared to parallel. Such stacked elements are promising candidates to be used as the basic logic cell for a new generation of Magnetic Random Access Memories (MRAM) [4, 5, 7, 9]. The perpetual increase in storage density as well as the increase in access time (now reaching the GHz regime) define two tasks for the physicist: (i) finding a system of reduced size such that the switching between two well defined micromagnetic configurations (corresponding to a “0” and “1”) is stable and repetitive, (ii) finding a mechanism by which this switching occurs on the nanosecond or sub-nanosecond time-scale.

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Authors and Affiliations

  1. URA CEA-CNRS SPINTEC CEA-Grenoble, 17 Avenue des Martyrs, 38054, Grenoble, France

    U. Ebels, L. D. Buda & I. L. Prejbeanu

  2. ICIS-CNR, Corso Stati Uniti 4, 35128, Padova, Italy

    M. Natali

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  1. U. Ebels
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  2. M. Natali
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Editors and Affiliations

  1. Universidade de Vigo, Vigo, Spain

    Luis M. Liz-Marzán

  2. Hahn-Meitner Institut Berlin, Germany

    Michael Giersig

  3. Poznan Technology University, Poznan, Poland

    Michael Giersig

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Ebels, U., Natali, M., Buda, L.D., Prejbeanu, I.L. (2003). Circular Magnetic Elements: Ground States, Reversal and Dipolar Interactions. In: Liz-Marzán, L.M., Giersig, M. (eds) Low-Dimensional Systems: Theory, Preparation, and Some Applications. NATO Science Series, vol 91. Springer, Dordrecht. https://doi.org/10.1007/978-94-010-0143-4_16

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