Cooperative and noncooperative magnetization reversal in alnicos

Skomski, Ralph; Ke, Liqin; Kramer, Matthew J.; Anderson, Iver E.; Wang, C. Z.; Zhang, W. Y.; Shield, Jeff E.; Sellmyer, D. J.

doi:10.1063/1.4976216

Title: Cooperative and noncooperative magnetization reversal in alnicos

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Abstract

Here, we investigate how magnetostatic interactions affect the coercivity of alnico-type magnets. Starting from exact micromagnetic relations, we also analyze two limits, namely cooperative reversal processes operative on short lengths scales and noncooperative reversal processes on long length scales. Furthermore, in alnicos, intrawire interactions are predominantly cooperative, whereas interwire effects are typically noncooperative. However, the transition between the regimes depends on feature size and hysteresis-loop shape, and interwire cooperative effects are largest for nearly rectangular loops. Our analysis revises the common shape-anisotropy interpretation of alnicos.

Authors:

Skomski, Ralph ^[1]; Ke, Liqin ^[2]; Kramer, Matthew J. ^[2]; Anderson, Iver E. ^[2]; Wang, C. Z. ^[2]; Zhang, W. Y. ^[1]; Shield, Jeff E. ^[2]; Sellmyer, D. J. ^[1]

Nebraska Center for Materials and Nanoscience and Department of Physics and Astronomy, University of Nebraska, Lincoln, Nebraska 68588, USA
Ames Laboratory, Iowa State University, Ames, Iowa 50011, USA

Publication Date:: Wed Feb 08 00:00:00 EST 2017

Research Org.:: Ames Lab., Ames, IA (United States)

Sponsoring Org.:: USDOE Office of Energy Efficiency and Renewable Energy (EERE), Vehicle Technologies Office (EE-3V); USDOE Office of Energy Efficiency and Renewable Energy (EERE), Office of Sustainable Transportation. Vehicle Technologies Office (VTO)

OSTI Identifier:: 1349347

Alternate Identifier(s):: OSTI ID: 1371885; OSTI ID: 1421275

Report Number(s):: IS-J 9354
Journal ID: ISSN 2158-3226; AAIDBI; 10.1063/1.4976216

Grant/Contract Number:: AC02-07CH11358

Resource Type:: Published Article

Journal Name:: AIP Advances

Additional Journal Information:: Journal Name: AIP Advances Journal Volume: 7 Journal Issue: 5; Journal ID: ISSN 2158-3226

Publisher:: American Institute of Physics

Country of Publication:: United States

Language:: English

Subject:: 36 MATERIALS SCIENCE

Citation Formats


                    Skomski, Ralph, Ke, Liqin, Kramer, Matthew J., Anderson, Iver E., Wang, C. Z., Zhang, W. Y., Shield, Jeff E., and Sellmyer, D. J. Cooperative and noncooperative magnetization reversal in alnicos.  United States: N. p., 2017. 
Web.  doi:10.1063/1.4976216.

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                    Skomski, Ralph, Ke, Liqin, Kramer, Matthew J., Anderson, Iver E., Wang, C. Z., Zhang, W. Y., Shield, Jeff E., & Sellmyer, D. J. Cooperative and noncooperative magnetization reversal in alnicos.  United States.  https://doi.org/10.1063/1.4976216

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                    Skomski, Ralph, Ke, Liqin, Kramer, Matthew J., Anderson, Iver E., Wang, C. Z., Zhang, W. Y., Shield, Jeff E., and Sellmyer, D. J. Wed .  
"Cooperative and noncooperative magnetization reversal in alnicos".  United States.  https://doi.org/10.1063/1.4976216.

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@article{osti_1349347,

  title        = {Cooperative and noncooperative magnetization reversal in alnicos},

  author       = {Skomski, Ralph and Ke, Liqin and Kramer, Matthew J. and Anderson, Iver E. and Wang, C. Z. and Zhang, W. Y. and Shield, Jeff E. and Sellmyer, D. J.},

  abstractNote = {Here, we investigate how magnetostatic interactions affect the coercivity of alnico-type magnets. Starting from exact micromagnetic relations, we also analyze two limits, namely cooperative reversal processes operative on short lengths scales and noncooperative reversal processes on long length scales. Furthermore, in alnicos, intrawire interactions are predominantly cooperative, whereas interwire effects are typically noncooperative. However, the transition between the regimes depends on feature size and hysteresis-loop shape, and interwire cooperative effects are largest for nearly rectangular loops. Our analysis revises the common shape-anisotropy interpretation of alnicos.},

  doi          = {10.1063/1.4976216},

  journal      = {AIP Advances},

  number       = 5,

  volume       = 7,

  place        = {United States},

  year         = {Wed Feb 08 00:00:00 EST 2017},

  month        = {Wed Feb 08 00:00:00 EST 2017}

}

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