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Title: Spin dynamics and frequency dependence of magnetic damping study in soft ferromagnetic FeTaC film with a stripe domain structure

Abstract

Perpendicular magnetic anisotropy (PMA) and low magnetic damping are the key factors for the free layer magnetization switching by spin transfer torque technique in magnetic tunnel junction devices. The magnetization precessional dynamics in soft ferromagnetic FeTaC thin film with a stripe domain structure was explored in broad band frequency range by employing micro-strip ferromagnetic resonance technique. The polar angle variation of resonance field and linewidth at different frequencies have been analyzed numerically using Landau-Lifshitz-Gilbert equation by taking into account the total free energy density of the film. The numerically estimated parameters Landé g-factor, PMA constant, and effective magnetization are found to be 2.1, 2 × 10{sup 5} erg/cm{sup 3} and 7145 Oe, respectively. The frequency dependence of Gilbert damping parameter (α) is evaluated by considering both intrinsic and extrinsic effects into the total linewidth analysis. The value of α is found to be 0.006 at 10 GHz and it increases monotonically with decreasing precessional frequency.

Authors:
; ;  [1]; ;  [2]
  1. Saha Institute of Nuclear Physics, 1/AF Bidhannagar, Calcutta 700 064 (India)
  2. Department of Physics, Indian Institute of Technology Guwahati, Guwahati - 781039 (India)
Publication Date:
OSTI Identifier:
22493917
Resource Type:
Journal Article
Resource Relation:
Journal Name: AIP Advances; Journal Volume: 5; Journal Issue: 6; Other Information: (c) 2015 Author(s); Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; ANISOTROPY; DAMPING; DOMAIN STRUCTURE; FERROMAGNETIC MATERIALS; FERROMAGNETIC RESONANCE; FREE ENERGY; FREQUENCY DEPENDENCE; GHZ RANGE; IRON COMPOUNDS; LANDE FACTOR; MAGNETIZATION; SPIN; SUPERCONDUCTING JUNCTIONS; TANTALUM CARBIDES; THIN FILMS; TUNNEL EFFECT; VARIATIONS

Citation Formats

Samantaray, B., E-mail: iitg.biswanath@gmail.com, Ranganathan, R., Mandal, P., Singh, Akhilesh K., and Perumal, A. Spin dynamics and frequency dependence of magnetic damping study in soft ferromagnetic FeTaC film with a stripe domain structure. United States: N. p., 2015. Web. doi:10.1063/1.4923290.
Samantaray, B., E-mail: iitg.biswanath@gmail.com, Ranganathan, R., Mandal, P., Singh, Akhilesh K., & Perumal, A. Spin dynamics and frequency dependence of magnetic damping study in soft ferromagnetic FeTaC film with a stripe domain structure. United States. doi:10.1063/1.4923290.
Samantaray, B., E-mail: iitg.biswanath@gmail.com, Ranganathan, R., Mandal, P., Singh, Akhilesh K., and Perumal, A. Mon . "Spin dynamics and frequency dependence of magnetic damping study in soft ferromagnetic FeTaC film with a stripe domain structure". United States. doi:10.1063/1.4923290.
@article{osti_22493917,
title = {Spin dynamics and frequency dependence of magnetic damping study in soft ferromagnetic FeTaC film with a stripe domain structure},
author = {Samantaray, B., E-mail: iitg.biswanath@gmail.com and Ranganathan, R. and Mandal, P. and Singh, Akhilesh K. and Perumal, A.},
abstractNote = {Perpendicular magnetic anisotropy (PMA) and low magnetic damping are the key factors for the free layer magnetization switching by spin transfer torque technique in magnetic tunnel junction devices. The magnetization precessional dynamics in soft ferromagnetic FeTaC thin film with a stripe domain structure was explored in broad band frequency range by employing micro-strip ferromagnetic resonance technique. The polar angle variation of resonance field and linewidth at different frequencies have been analyzed numerically using Landau-Lifshitz-Gilbert equation by taking into account the total free energy density of the film. The numerically estimated parameters Landé g-factor, PMA constant, and effective magnetization are found to be 2.1, 2 × 10{sup 5} erg/cm{sup 3} and 7145 Oe, respectively. The frequency dependence of Gilbert damping parameter (α) is evaluated by considering both intrinsic and extrinsic effects into the total linewidth analysis. The value of α is found to be 0.006 at 10 GHz and it increases monotonically with decreasing precessional frequency.},
doi = {10.1063/1.4923290},
journal = {AIP Advances},
number = 6,
volume = 5,
place = {United States},
year = {Mon Jun 15 00:00:00 EDT 2015},
month = {Mon Jun 15 00:00:00 EDT 2015}
}
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