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Title: Ferromagnetic resonance linewidth in metallic thin films: Comparison of measurement methods

Abstract

Stripline (SL), vector network analyzer (VNA), and pulsed inductive microwave magnetometer (PIMM) techniques were used to measure the ferromagnetic resonance (FMR) linewidth for a series of Permalloy films with thicknesses of 50 and 100 nm. The SL-FMR measurements were made for fixed frequencies from 1.5 to 5.5 GHz. The VNA-FMR and PIMM measurements were made for fixed in-plane fields from 1.6 to 8 kA/m (20-100 Oe). The results provide a confirmation, lacking until now, that the linewidths measured by these three methods are consistent and compatible. In the field format, the linewidths are a linear function of frequency, with a slope that corresponds to a nominal Landau-Lifshitz phenomenological damping parameter {alpha} value of 0.007 and zero frequency intercepts in the 160-320 A/m (2-4 Oe) range. In the frequency format, the corresponding linewidth versus frequency response shows a weak upward curvature at the lowest measurement frequencies and a leveling off at high frequencies.

Authors:
; ; ; ; ; ; ;  [1];  [2];  [2]
  1. Department of Physics, Colorado State University, Fort Collins, Colorado 80523 (United States)
  2. (United States)
Publication Date:
OSTI Identifier:
20795804
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Applied Physics; Journal Volume: 99; Journal Issue: 9; Other Information: DOI: 10.1063/1.2197087; (c) 2006 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; FERROMAGNETIC MATERIALS; FERROMAGNETIC RESONANCE; GHZ RANGE 01-100; MAGNETOMETERS; MICROWAVE RADIATION; PERMALLOY; THIN FILMS

Citation Formats

Kalarickal, Sangita S., Krivosik, Pavol, Wu, Mingzhong, Patton, Carl E., Schneider, Michael L., Kabos, Pavel, Silva, T.J., Nibarger, John P., National Institute of Standards and Technology, Boulder, Colorado 80305, and Sun Microsystems, One StorageTek Drive, Louisville, Colorado 80028. Ferromagnetic resonance linewidth in metallic thin films: Comparison of measurement methods. United States: N. p., 2006. Web. doi:10.1063/1.2197087.
Kalarickal, Sangita S., Krivosik, Pavol, Wu, Mingzhong, Patton, Carl E., Schneider, Michael L., Kabos, Pavel, Silva, T.J., Nibarger, John P., National Institute of Standards and Technology, Boulder, Colorado 80305, & Sun Microsystems, One StorageTek Drive, Louisville, Colorado 80028. Ferromagnetic resonance linewidth in metallic thin films: Comparison of measurement methods. United States. doi:10.1063/1.2197087.
Kalarickal, Sangita S., Krivosik, Pavol, Wu, Mingzhong, Patton, Carl E., Schneider, Michael L., Kabos, Pavel, Silva, T.J., Nibarger, John P., National Institute of Standards and Technology, Boulder, Colorado 80305, and Sun Microsystems, One StorageTek Drive, Louisville, Colorado 80028. Mon . "Ferromagnetic resonance linewidth in metallic thin films: Comparison of measurement methods". United States. doi:10.1063/1.2197087.
@article{osti_20795804,
title = {Ferromagnetic resonance linewidth in metallic thin films: Comparison of measurement methods},
author = {Kalarickal, Sangita S. and Krivosik, Pavol and Wu, Mingzhong and Patton, Carl E. and Schneider, Michael L. and Kabos, Pavel and Silva, T.J. and Nibarger, John P. and National Institute of Standards and Technology, Boulder, Colorado 80305 and Sun Microsystems, One StorageTek Drive, Louisville, Colorado 80028},
abstractNote = {Stripline (SL), vector network analyzer (VNA), and pulsed inductive microwave magnetometer (PIMM) techniques were used to measure the ferromagnetic resonance (FMR) linewidth for a series of Permalloy films with thicknesses of 50 and 100 nm. The SL-FMR measurements were made for fixed frequencies from 1.5 to 5.5 GHz. The VNA-FMR and PIMM measurements were made for fixed in-plane fields from 1.6 to 8 kA/m (20-100 Oe). The results provide a confirmation, lacking until now, that the linewidths measured by these three methods are consistent and compatible. In the field format, the linewidths are a linear function of frequency, with a slope that corresponds to a nominal Landau-Lifshitz phenomenological damping parameter {alpha} value of 0.007 and zero frequency intercepts in the 160-320 A/m (2-4 Oe) range. In the frequency format, the corresponding linewidth versus frequency response shows a weak upward curvature at the lowest measurement frequencies and a leveling off at high frequencies.},
doi = {10.1063/1.2197087},
journal = {Journal of Applied Physics},
number = 9,
volume = 99,
place = {United States},
year = {Mon May 01 00:00:00 EDT 2006},
month = {Mon May 01 00:00:00 EDT 2006}
}
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