High coercivity in large exchange-bias Co/CoO-MgO nano-granular films

doi:10.1088/1674-1056/24/3/034501

Abstract

We present a detailed study on the magnetic coercivity of Co/CoO-MgO core-shell systems, which exhibits a large exchange bias due to an increase of the uncompensated spin density at the interface between the CoO shell and the metallic Co core by replacing Co by Mg within the CoO shell. We find a large magnetic coercivity of 7120 Oe around the electrical percolation threshold of the Co/CoO core/shell particles, while samples with a smaller or larger Co metal volume fraction show a considerably smaller coercivity. Thus, this study may lead to a route to improving the magnetic properties of artificial magnetic material in view of potential applications.

Keywords: granular films exchange bias coercivity

Received: 25 September 2014
Revised: 27 October 2014
Accepted manuscript online:

PACS:	45.70.Cc	(Static sandpiles; granular compaction)
	75.30.Et	(Exchange and superexchange interactions)
	75.50.Vv	(High coercivity materials)
	75.60.Ej	(Magnetization curves, hysteresis, Barkhausen and related effects)

Fund:

Project supported by the National Basic Research Program of China (Grant No. 2012CB932304), the National Natural Science Foundation of China (Grant Nos. U1232210, 91122035, 11174124, and 11374137), the Natural Science Foundation of the Jiangsu Higher Education Institutions of China (Grant No. 14KJB140003), and the Priority Academic Program Development of Jiangsu Higher Education Institutions, China.

Corresponding Authors: Wan Xian-Gang
E-mail: xgwan@nju.edu.cn

Cite this article:

Ge Chuan-Nan (葛传楠), Wan Xian-Gang (万贤纲), Eric Pellegrin, Hu Zhi-Wei (胡志伟), Wen-I Liang, Michael Bruns, Zou Wen-Qin (邹文琴), Du You-Wei (都有为) High coercivity in large exchange-bias Co/CoO-MgO nano-granular films 2015 Chin. Phys. B 24 034501

[1]	Nogués J, Sort J, Langlais V, Skumryeva V, Suriñach S, Muñoz J S and Baró M D 2005 Phys. Rep. 422 65
[2]	Skumryev V, Stoyanov S, Zhang Y, Hadjipanayis G, Givord D and Nogués J 2003 Nature 423 850
[3]	Meiklejohn W H and Bean C P 1956 Phys. Rev. 102 1413
[4]	Cheng Z H, Luo Y and Zhao G P 2013 Acta Phys. Sin. 62 176102 (in Chinese)
[5]	Zhang H W, Zhou W P and Liu E K 2013 Acta Phys. Sin. 62 147501 (in Chinese)
[6]	Shi Z, Du J and Zhou S M 2014 Chin. Phys. B 23 027503
[7]	Hong J I, Leo T, Smith D J and Berkowitz A E 2006 Phys. Rev. Lett. 96 117204
[8]	Nogués J, Leighton C and Schuller I K 2000 Phys. Rev. B 61 1315
[9]	Sort J, Suriñach S, Muñoz J S, Baró M D, Nogués J, Chouteau G, Skumryev V and Hadjipanayis G C 2002 Phys. Rev. B 65 174420
[10]	Ohldag H, Scholl A, Nolting F, Arenholz E, Maat S, Young A T, Carey M and Stöhr J 2003 Phys. Rev. Lett. 91 017203
[11]	Sort J, Nogués J, Amils X, Suriñach S, Muñoz J S and Baró M D 1999 Appl. Phys. Lett. 75 3177
[12]	Sort J, Langlais V, Doppiu S, Dieny B, Suriñach S, Muñoz J S, Baró M D, Laurent Ch and Nogués J 2004 Nanotechnology 15 211
[13]	Sort J, Nogués J, Suriñach S, Muñoz J S, Baró M D, Chappel E, Dupont F and Chouteau G 2001 Appl. Phys. Lett. 79 1142
[14]	Hou Z P, Su F and Wang W Q 2014 Acta Phys. Sin. 63 087501 (in Chinese)
[15]	Xiao G and Chien C L 1988 J. Appl. Phys. 63 4252
[16]	Zheng N, Abdul Q and Ram C 2011 Chin. Phys. Lett. 28 098301
[17]	Abeles B, Sheng P, Coutts M D and Arie Y 1975 Adv. Phys. 24 407
[18]	Burnus T, Hu Z, Hsieh H H, Joly V L J, Joy P A, Haverkort M W, Wu H, Tanaka A, Lin H J, Chen C T and Tjeng L H 2008 Phys. Rev. B 77 125124
[19]	Ge C, Wan X, Pellegrin E, Hu Z, Valvidares M, Barla A, Liang W I, Chu Y H, Zou W and Du Y 2013 Nanoscale 5 10236
[20]	Nakagawa T, Takagi Y and Yokoyama T 2012 Phys. Rev. B 86 144418
[21]	Tamion A, Raufast C, Hillenkamp M, Bonet E, Jouanguy J, Canut B, Bernstein E, Boisron O, Wernsdorfer W and Dupuis V 2010 Phys. Rev. B 81 144403
[22]	Jamet M, Wernsdorfer W, Thirion C, Mailly D, Dupuis V, Mélinon P and Pérez A 2001 Phys. Rev. Lett. 86 4767
[23]	Rusponi S, Cren T, Weiss N, Epple M, Buluschek P, Claude L and Brune H 2003 Nat. Mater. 2 546
[24]	Del Bianco L, Boscherini F, Fiorini A L, Tamisari M, Spizzo F, Vittori A M and Piscopiello E 2008 Phys. Rev. B 77 094408
[25]	Gittleman J I, Abeles B and Bozowski S 1974 Phys. Rev. B 9 3891
[26]	Leighton C, Nogueś J, Jonsson-Åkerman B J and Schuller I K 2000 Phys. Rev. Lett. 84 3466
[27]	Nogués J, Lederman D, Moran T J and Schuller I K 1996 Phys. Rev. Lett. 76 4624
[28]	Domingo N, Testa A M, Fiorani D, Binns C, Baker S and Tejada J 2007 J. Magn. Magn. Mater. 316 155

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High coercivity in large exchange-bias Co/CoO-MgO nano-granular films

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