Broad-band FMR study of ferromagnetic thin films patterned with antidot lattices

被引：12

作者：

Bhat, V. ^{[1
]}

Woods, J. ^{[1
]}

De Long, L. E. ^{[1
]}

Hastings, J. T. ^{[2
]}

Metlushko, V. V. ^{[3
]}

Rivkin, K. ^{[4
]}

Heinonen, O. ^{[5
]}

Sklenar, J. ^{[6
]}

Ketterson, J. B. ^{[6
]}

机构：

[1] Univ Kentucky, Dept Phys & Astron, Lexington, KY 40506 USA

[2] Univ Kentucky, Dept Elect & Comp Engn, Lexington, KY 40506 USA

[3] Univ Illinois, Dept Elect & Comp Engn, Chicago, IL 60607 USA

[4] Seagate Technol, Bloomington, MN 55435 USA

[5] Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA

[6] Northwestern Univ, Dept Phys & Astron, Evanston, IL 60208 USA

来源：

PHYSICA C-SUPERCONDUCTIVITY AND ITS APPLICATIONS | 2012年 / 479卷

关键词：

Ferromagnetic vortices; Domain wall pinning; Ferromagnetic resonance; Ferromagnetic antidot arrays; Micromagnetic simulations; ARRAYS; RESONANCE;

D O I：

10.1016/j.physc.2012.02.003

中图分类号：

O59 [应用物理学];

学科分类号：

摘要：

Previous ferromagnetic resonance (FMR) studies of ferromagnetic (FM) thin films patterned with antidot (AD) arrays have generally avoided the low-field, hysteretic regime that is dominated by irreversible domain wall (DW) dynamics in unpatterned films. Moreover, FM vortices have not yet been identified and systematically studied in films patterned with AD lattices (ADLs). We have studied DC magnetization and broad-band FMR data for permalloy thin films of thickness t approximate to 25 nm, patterned with square lattices of square-shaped AD of width D and separation d = 1000 nm. We observe highly reproducible magnetic hysteresis curves and FMR spectra in the low-field reversal regime (i.e., applied magnetic fields H < H-C, where HC is the coercive field), which indicates the ADL enforces a reproducible evolution of spin textures compared to the more random behavior of DW evolution in unpatterned films. The width of the reversal regime (2H(C)) and the field separation between observed FMR modes increases with D for a fixed separation d. Our micromagnetic simulations suggest these effects are consequences of both edge pinning of moments by individual AD, or DW pinning by the extended ADL, which involves two distinct length scales L approximate to d and L >> d, respectively. FM vortices are observed in our simulations, and their stability sensitively depends upon the AD size and applied magnetic field history. (C) 2012 Elsevier B. V. All rights reserved.

引用

页码：83 / 87

页数：5

共 16 条

[11] Analysis of ferromagnetic resonance response of square arrays of permalloy nanodots [J].

Rivkin, K. ;

Xu, Wentao ;

De Long, L. E. ;

Metlushko, V. V. ;

Ilic, B. ;

Ketterson, J. B. .

JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS, 2007, 309 (02) :317-325

[12] Resonant modes of dipole-coupled lattices [J].

Rivkin, K ;

Heifetz, A ;

Sievert, PR ;

Ketterson, JB .

PHYSICAL REVIEW B, 2004, 70 (18) :1-9

[13] Dynamic magnetic response of infinite arrays of ferromagnetic particles [J].

Rivkin, Kirill ;

Saslow, W. ;

De Long, L. E. ;

Ketterson, J. B. .

PHYSICAL REVIEW B, 2007, 75 (17)

[14] Micromagnetic tailoring of periodic antidot permalloy arrays for high density storage [J].

Torres, L ;

Lopez-Diaz, L ;

Iñiguez, J .

APPLIED PHYSICS LETTERS, 1998, 73 (25) :3766-3768

[15] Microwave absorption measurements using a broad-band meanderline approach [J].

Tsai, C. C. ;

Choi, J. ;

Cho, Sunglae ;

Lee, S. J. ;

Sarma, B. K. ;

Thompson, C. ;

Chernyashevskyy, O. ;

Nevirkovets, I. ;

Ketterson, J. B. .

REVIEW OF SCIENTIFIC INSTRUMENTS, 2009, 80 (02)

[16] Ferromagnetic resonance study of nanoscale ferromagnetic ring lattices [J].

Xu, WT ;

Watkins, DB ;

DeLong, LE ;

Rivkin, K ;

Ketterson, JB ;

Metlushko, VV .

JOURNAL OF APPLIED PHYSICS, 2004, 95 (11) :6645-6647

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