應用於圖樣化及熱輔助磁記錄之具(001)優選取向的序化鐵鉑交互彈簧磁體

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研究生：	廖容蔚 Liao, Jung-Wei
論文名稱：	應用於圖樣化及熱輔助磁記錄之具(001)優選取向的序化鐵鉑交互彈簧磁體 (001)-oriented L10 FePt exchange spring magnets for bit-patterned and heat-assisted magnetic recording
指導教授：	賴志煌 Lai, Chih-Huang
口試委員:	許仁華 Jen-Hwa Hsu 黃志青 Jacob Chih-Ching Huang 林秀豪 Hsiu-Hau Lin 黃迪靖 Di-Jing Huang
學位類別：	博士 Doctor
系所名稱：	工學院 - 材料科學工程學系 Materials Science and Engineering
論文出版年：	2014
畢業學年度：	102
語文別：	英文
論文頁數：	109
中文關鍵詞：	磁記錄媒體、鐵鉑、熱輔助、圖樣化、交互彈簧磁體
外文關鍵詞：	Magnetic recording media, FePt, Heat-assisted, Bit-patterned, Exchange spring magnet
相關次數：	點閱：2 下載：0
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圖樣化與熱輔助磁記錄媒體擁有記錄密度超過1 Terabits/in2的潛力，而具有(001)優選取向的序化鐵鉑交互彈簧磁體為實現其記錄媒體的重要基石。在本論文中我們首先在實驗上實現此交互彈簧磁體，進而在實驗與理論上研究其磁體內部的磁矩翻轉模式。實驗結果顯示在單一鐵鉑膜層中其序化伴隨著薄膜的團聚行為，導致於一序化但具有不規則孔洞的薄膜，無法利用其薄膜進一步製備圖樣化磁記錄媒體。藉由引入氧化鐵的覆蓋層我們可以在保有序化行為下抑制其薄膜團聚，成功地得到一連續、序化且具有(001)優選取向的鐵鉑薄膜。接著，我們使用原子自旋模型研究一具有軟磁邊緣的鐵鉑圖樣點內磁矩翻轉模式；其軟磁邊緣可能由於在圖樣化連續鐵鉑薄膜成奈米點的過程中產生的附加傷害而形成。計算結果顯示在不同的邊緣寬度下磁矩皆藉由成核的方式翻轉；隨著邊緣寬度的增加翻轉行為由個別的成核轉變成多個位置一起成核，而所需的成核磁場隨之降低然後飽和。在相對薄的軟磁邊緣下個別的成核行為可進一步由滴狀和反滴狀模型描述。最後，我們研究在具有不同軟磁層的居里溫度之序化鐵鉑交互彈簧磁體內磁矩翻轉行為；在熱輔助磁記錄媒體內其軟磁層的居里溫度影響高溫下熱導入寫入錯誤的大小，而軟磁膜層厚度的增加將降低加熱效率。研究結果顯示對於達成磁區壁輔助翻轉所需的軟磁膜層厚度和其居里溫度成正比，且其薄膜厚度將隨著寫入溫度地上升而進一步增加。由於增加的軟磁膜層厚度將犧牲熱輔助寫入所需的加熱效率，在保有足夠加熱效率的熱輔助寫入下將難以達成磁區壁輔助翻轉。所有結果建議著在圖樣化與熱輔助磁記錄媒體中為了保有其加熱效率，我們需引入一薄的軟磁層薄膜，而磁區壁輔助翻轉可能藉由軟磁邊緣的幫助來達成。

For bit-patterned and heat-assisted magnetic recording media, the essential basis is the (001) textured L10 FePt exchange spring magnet. In this dissertation we firstly realize this spring magnet and then investigate the corresponding magnetization reversal modes. We show that in a single-layered FePt film the L10 ordering is accompanied by the film agglomeration, resulting in the ordered but ruptured film. By introducing an FeOx capping layer we can suppress the film agglomeration while preserve the L10 ordering, leading to the desired continuous and (001)-oriented L10 FePt layer. Using the atomistic spin model we then investigate the magnetization reversal modes in the L10 FePt patterned dot with the soft magnetic edge, which could be caused by patterning damage. We show that the nucleation dominates the magnetization reversal at all studied edge-widths. As the edge-width increases the individual nucleation event, which can be described by the droplet and the antidroplet, turns into the multiple nucleation events, and the required nucleation field decreases and saturates. Finally, we investigate the magnetization reversal behaviors in L10 FePt exchange spring magnets with soft magnetic layers of varied Curie temperature (Tc), which are crucial for the thermally induced error. We show that for the domain-wall assisted reversal the increased Tc of the soft layer increases the required soft-layer thickness, which further increases at elevated temperatures. For the heat-assisted magnetic recording the increased soft-layer thickness sacrifices the heat efficiency and is therefore undesirable. All the results indicate that in the bit-patterned and heat-assisted recording media, a thin soft magnetic layer preserves the heat efficiency, and the soft magnetic edges with controllable properties could achieve the domain-wall assisted reversal.

Abstract . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . I
Abstract in Chinese . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . III
Acknowledgement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . V
Table of contents . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . VII
List of gures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . XI
List of tables . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .XIX
List of abbreviations and symbols . . . . . . . . . . . . . . . . . . . . . . . . .XXI
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
1 Motivation . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
2 Outline of the dissertation . . . . . . . . . . . . . . . . . . 4
Literature review. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
1 Modern magnetic recording technology . . . . . . . . . . . 6
1.1 Fundamental principle . . . . . . . . . . . . . . . . 6
1.2 Trilemma of magnetic recording . . . . . . . . . . . 8
2 Next generation of storage technology . . . . . . . . . . . . 10
2.1 Bit-patterned magnetic recording . . . . . . . . . . 10
2.2 L10 FePt . . . . . . . . . . . . . . . . . . . . . . . . 12
2.3 Write-assist technique . . . . . . . . . . . . . . . . 14
Experimental and modeling techniques . . . . . . . . . . . . . . . . 17
1 Sample fabrication . . . . . . . . . . . . . . . . . . . . . . 18
1.1 Magnetron sputtering system . . . . . . . . . . . . 18
1.2 Rapid thermal annealing system . . . . . . . . . . . 19
1.3 Inductively coupled plasma etching system . . . . . 20
2 Structure characterization . . . . . . . . . . . . . . . . . . 21
2.1 X-ray diractometer . . . . . . . . . . . . . . . . . 21
2.2 Transmission electron microscope . . . . . . . . . . 22
2.3 Scanning electron microscope . . . . . . . . . . . . 23
3 Composition characterization . . . . . . . . . . . . . . . . 24
3.1 X-ray absorption spectroscopy . . . . . . . . . . . . 24
4 Magnetic characterization . . . . . . . . . . . . . . . . . . 25
4.1 Vibrating sample magnetometer . . . . . . . . . . . 25
4.2 Superconducting quantum interference device vibrating sample magnetometer . . . . . . . . . . . . 26
5 Modeling of magnetic materials . . . . . . . . . . . . . . . 27
5.1 Atomistic spin model . . . . . . . . . . . . . . . . . 27
Highly (001)-oriented and continuous L10 FePt film by introducing an FeOx cap layer . . . . . . . . . . . . . . . . . . . . . . . . . 29
1 Purpose of study . . . . . . . . . . . . . . . . . . . . . . . 30
2 Experimental . . . . . . . . . . . . . . . . . . . . . . . . . 32
3 Results and discussion . . . . . . . . . . . . . . . . . . . . 34
3.1 Ta capped FePt lms . . . . . . . . . . . . . . . . . 34
3.2 FeOx capped FePt lms . . . . . . . . . . . . . . . 35
3.3 L10 ordering, agglomeration, and easy-axis orientation in capped FePt films . . . . . . . . . . . . . 40
4 Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . 43
Magnetization reversal modes in L10 FePt nano dots with magnetically soft edges . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45
1 Purpose of study . . . . . . . . . . . . . . . . . . . . . . . 46
2 Atomistic spin model . . . . . . . . . . . . . . . . . . . . . 48
3 Results and discussion . . . . . . . . . . . . . . . . . . . . 51
3.1 Narrow soft edge: single-droplet to antidroplet nucleation. . . . . . . . . . .54
3.2 Wide soft edge: an incomplete to a complete circular domain wall . . . . . 60
3.3 Thermally induced switching eld distribution . . . 62
3.4 Eect of interfacial exchange coupling on the reversal modes . . . . . . . . .64
4 Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . 67
Temperature-dependent magnetization reversal characteristics in (001)-oriented L10 FePt exchange spring magnets with soft magnetic layers of varied Curie temperature . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .69
1 Purpose of study . . . . . . . . . . . . . . . . . . . . . . . 70
2 Experimental and atomistic spin model . . . . . . . . . . . 72
3 Results and discussion . . . . . . . . . . . . . . . . . . . . 76
3.1 Experimental properties at temperatures ranged from 300 to 473 K . . . 76
3.2 Calculated properties at temperatures ranged from 300 to 600 K . . . . . 79
4 Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . 83
Conclusions and suggestions for future work . . . . . . . . . . . 85
1 Conclusions . . . . . . . . . . . . . . . . . . . . . . . . . . 86
2 Suggestions for future work . . . . . . . . . . . . . . . . . 88
Bibliography . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 89
Curriculum vitae . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 105
                                

[1] Dataerasure. Computer hard drive. [Online]. Available: http://www.dataerasure.com/computer hard drive.php
[2] T. B. Massalski, Binary alloy phase diagrams. ASM International, 1990, p.1752.
[3] JOEL. JEM-2100F field emission electron microscope. [On- line]. Available: http://www.jeol.co.jp/en/products/detail/JEM- 2100F.html
[4] JOEL. JEM-7600F schottky field emission scan- ning electron microscope. [Online]. Available: http://www.jeol.co.jp/en/products/detail/JSM-7600F.html
[5]Q. Design. Magnetic property measurement system. [On- line]. Available: http://www.qd-americadosul.com/mpms-squid- vsm-specifications.html
[6] D. Weller, O. Mosendz, G. Parker, S. Pisana, and T. S. Santos, “L10 FePtX–Y media for heat-assisted magnetic recording,” physica status solidi (a), vol. 210, no. 7, pp. 1245–1260, 2013.
[7] D. Weller and A. Moser, “Thermal effect limits in ultrahigh-density magnetic recording,” Magnetics, IEEE Transactions on, vol. 35, no. 6, pp. 4423–4439, 1999.
[8] R. L. White, R. Newt, and R. F. W. Pease, “Patterned media: a viable route to 50 Gbit/in2 and up for magnetic recording?” Mag- netics, IEEE Transactions on, vol. 33, no. 1, pp. 990–995, Jan 1997.
[9] O. A. Ovanov, L. V. Solina, and V. A. Demshina, “Determination of the anisotropy constant and saturation magnetization, and mag- netic properties of powders of an iron-platinum alloy,” The Physics of Metals and Metallography, vol. 35, pp. 81–85, 1973.
[10] C. Chappert, H. Bernas, J. Ferr ́e, V. Kottler, J.-P. Jamet, Y. Chen, E. Cambril, T. Devolder, F. Rousseaux, V. Mathet, and H. Launois, “Planar patterned magnetic media obtained by ion irradiation,” Sci- ence, vol. 280, no. 5371, pp. 1919–1922, 1998.
[11] T. W. McDaniel, “Ultimate limits to thermally assisted magnetic recording,” Journal of Physics: Condensed Matter, vol. 17, no. 7, p. R315, 2005.
[12] R. Rottmayer, S. Batra, D. Buechel, W. Challener, J. Hohlfeld, Y. Kubota, L. Li, B. Lu, C. Mihalcea, K. Mountfield, K. Pelhos, C. Peng, T. Rausch, M. A. Seigler, D. Weller, and X. Yang, “Heat- assisted magnetic recording,” Magnetics, IEEE Transactions on, vol. 42, no. 10, pp. 2417–2421, 2006.
[13] R. F. L. Evans, R. W. Chantrell, U. Nowak, A. Lyberatos, and H.-J. Richter, “Thermally induced error: Density limit for magnetic data storage,” Applied Physics Letters, vol. 100, no. 10, p. 102402, 2012.
[14] H. J. Richter, A. Lyberatos, U. Nowak, R. F. L. Evans, and R. W. Chantrell, “The thermodynamic limits of magnetic record- ing,” Journal of Applied Physics, vol. 111, no. 3, p. 033909, 2012.
[15] D. Suess and T. Schrefl, “Breaking the thermally induced write error in heat assisted recording by using low and high Tc materials,” Applied Physics Letters, vol. 102, no. 16, p. 162405, 2013.
[16] S. Hussain, C. S. Bhatia, H. Yang, and A. J. Danner, “Effect of fept on resonant behaviour of a near field transducer for high areal density heat assisted magnetic recording,” Applied Physics Letters, vol. 104, no. 11, p. 111107, 2014.
[17] S. Iwasaki, “Perpendicular magnetic recording,” Magnetics, IEEE Transactions on, vol. 16, no. 1, pp. 71–76, Jan 1980.
[18] T. Oikawa, M. Nakamura, H. Uwazumi, T. Shimatsu, H. Mu- raoka, and Y. Nakamura, “Microstructure and magnetic proper- ties of CoPtCr−SiO2 perpendicular recording media,” in Magnetics Conference, 2002. INTERMAG Europe 2002. Digest of Technical Papers. 2002 IEEE International, April 2002, pp. FQ2–.
[19] V. B. Minuhin, “Modulation noise in thin-film metallic media: el- ements of pulse/transition modulation theory,” Magnetics, IEEE Transactions on, vol. 36, no. 4, pp. 2077–2090, Jul 2000.
[20] B. Slutsky and H. Bertram, “Transition noise analysis of thin film magnetic recording media,” Magnetics, IEEE Transactions on, vol. 30, no. 5, pp. 2808–2817, Sep 1994.
[21] E. Goto, N. Hayashi, T. Miyashita, and K. Nakagawa, “Magnetiza- tion and switching characteristics of composite thin magnetic films,” Journal of Applied Physics, vol. 36, no. 9, pp. 2951–2958, 1965.
[22] H. Richter, “Density limits imposed by the microstructure of mag- netic recording media,” Journal of Magnetism and Magnetic Mate- rials, vol. 321, no. 6, pp. 467 – 476, 2009.
[23] H. J. Richter, A. Y. Dobin, R. T. Lynch, D. Weller, R. M. Brockie, O. Heinonen, K. Z. Gao, J. Xue, R. J. M. v. d. Veerdonk, P. Asselin, and M. F. Erden, “Recording potential of bit-patterned media,” Applied Physics Letters, vol. 88, no. 22, p. 222512, 2006.
[24] A. T. McCallum, P. Krone, F. Springer, C. Brombacher, M. Al- brecht, E. Dobisz, M. Grobis, D. Weller, and O. Hellwig, “L10 FePt based exchange coupled composite bit patterned films,” Ap- plied Physics Letters, vol. 98, no. 24, p. 242503, 2011.
[25] T. Shimatsu, Y. Inaba, H. Kataoka, J. Sayama, H. Aoi, S. Okamoto, and O. Kitakami, “Dot arrays of L10-type FePt ordered alloy per- pendicular films fabricated using low-temperature sputter film de- position,” Journal of Applied Physics, vol. 109, no. 7, p. 07B726, 2011.
[26] H. Wang, M. T. Rahman, H. Zhao, Y. Isowaki, Y. Kamata, A. Kik- itsu, and J.-P. Wang, “Fabrication of FePt type exchange coupled composite bit patterned media by block copolymer lithography,” Journal of Applied Physics, vol. 109, no. 7, p. 07B754, 2011.
[27] T. Bublat and D. Goll, “Large-area hard magnetic L10 - FePt nanopatterns by nanoimprint lithography,” Nanotechnology, vol. 22, no. 31, p. 315301, 2011.
[28] A. T. McCallum, D. Kercher, J. Lille, D. Weller, and O. Hellwig, “Prevention of dewetting during annealing of FePt films for bit pat- terned media applications,” Applied Physics Letters, vol. 101, no. 9, p. 092402, 2012.
[29] X. Gu, P. Dorsey, and T. P. Russell, “High density and large area arrays of silicon oxide pillars with tunable domain size for mask etch applications,” Advanced Materials, vol. 24, no. 40, pp. 5505–5511, 2012.
[30] K. Barmak, J. Kim, D. C. Berry, W. N. Hanani, K. Wierman, E. B. Svedberg, and J. K. Howard, “Calorimetric studies of the A1 to L10 transformation in binary FePt thin films with compositions in the range of 47.5–54.4 at.% Fe,” Journal of Applied Physics, vol. 97, no. 2, p. 024902, 2005.
[31] J.-S. Kim, Y.-M. Koo, B.-J. Lee, and S.-R. Lee, “The origin of (001) texture evolution in FePt thin films on amorphous substrates,” Journal of Applied Physics, vol. 99, no. 5, p. 053906, 2006.
[32] L.-W. Wang, W.-C. Shih, Y.-C. Wu, and C.-H. Lai, “Promotion of [001]-oriented L10-FePt by rapid thermal annealing with light ab- sorption layer,” Applied Physics Letters, vol. 101, no. 25, p. 252403, 2012.
[33] W. A. Challener, C. Peng, A. V. Itagi, D. Karns, W. Peng, Y. Peng, X. Yang, X. Zhu, N. J. Gokemeijer, Y.-T. Hsia, G. Ju, R. E. Rottmayer, M. A. Seigler, and E. C. Gage, “Heat-assisted magnetic recording by a near-field transducer with efficient optical energy transfer,” Nature Photonics, vol. 3, p. 220, 2009.
[34] B. C. Stipe, T. C. Strand, C. C. Poon, H. Balamane, T. D. Boone, J. A. Katine, J.-L. Li, V. Rawat, H. Nemoto, A. Hirotsune, O. Hell- wig, R. Ruiz, E. Dobisz, D. S. Kercher, N. Robertson, T. R. Al- brecht, and B. D. Terris, “Magnetic recording at 1.5 pb m−2 using an integrated plasmonic antenna,” Nature Photonics, vol. 4, p. 484, 2010.
[35] A. Y. Dobin and H. J. Richter, “Domain wall assisted magnetic recording,” Applied Physics Letters, vol. 89, no. 6, p. 062512, 2006.
[36] D. Suess, J. Lee, J. Fidler, and T. Schrefl, “Exchange-coupled per- pendicular media,” Journal of Magnetism and Magnetic Materials, vol. 321, no. 6, pp. 545 – 554, 2009.
[37] R. F. L. Evans, W. J. Fan, P. Chureemart, T. A. Ostler, M. O. A. Ellis, and R. W. Chantrell, “Atomistic spin model simulations of magnetic nanomaterials,” Journal of Physics: Condensed Matter, vol. 26, no. 10, p. 103202, 2014.
[38]vampire software package, version 3. Available from http://vampire.york.ac.uk/.
[39] G. van der Laan and I. W. Kirkman, “The 2p absorption spectra of 3d transition metal compounds in tetrahedral and octahedral symmetry,” Journal of Physics: Condensed Matter, vol. 4, no. 16, p. 4189, 1992.
[40] P. W. Anderson and J. M. Rowell, “Probable observation of the josephson superconducting tunneling effect,” Physics Review Let- ters, vol. 10, pp. 230–232, Mar 1963.
[41] B. D. Terris and T. Thomson, “Nanofabricated and self-assembled magnetic structures as data storage media,” Journal of Physics D: Applied Physics, vol. 38, no. 12, p. R199, 2005.
[42] H. J. Richter, A. Y. Dobin, R. T. Lynch, D. Weller, R. M. Brockie, O. Heinonen, K. Z. Gao, J. Xue, R. J. M. v. d. Veerdonk, P. Asselin, and M. F. Erden, “Recording potential of bit-patterned media,” Applied Physics Letters, vol. 88, no. 22, p. 222512, 2006.
[43] Y. K. Takahashi, M. Ohnuma, and K. Hono, “Low-temperature fabrication of high-coercivity L10 ordered FePt magnetic thin films by sputtering,” Japanese Journal of Applied Physics, vol. 40, no. Part 2, No. 12B, pp. L1367–L1369, 2001.
[44] M. Delalande, M. J.-F. Guinel, L. F. Allard, A. Delattre, R. Le Bris, Y. Samson, P. Bayle-Guillemaud, and P. Reiss, “L10 ordering of ultrasmall FePt nanoparticles revealed by TEM in situ annealing,” The Journal of Physical Chemistry C, vol. 116, no. 12, pp. 6866– 6872, 2012.
[45] D. J. Srolovitz and S. A. Safran, “Capillary instabilities in thin films. ii. Kinetics,” Journal of Applied Physics, vol. 60, no. 1, 1986.
[46] A. Perumal, Y. K. Takahashi, T. O. Seki, and K. Hono, “Particu- late structure of L10 ordered ultrathin FePt films for perpendicular recording,” Applied Physics Letters, vol. 92, no. 13, p. 132508, 2008.
[47] T. Shima, K. Takanashi, Y. K. Takahashi, and K. Hono, “Coerciv- ity exceeding 100kOe in epitaxially grown FePt sputtered films,” Applied Physics Letters, vol. 85, no. 13, 2004.
[48] Y.-C. Wu, L.-W. Wang, M. T. Rahman, and C.-H. Lai, “Evolution of granular to particulate structure of (001) FePt on amorphous substrates (invited),” Journal of Applied Physics, vol. 103, no. 7, p. 07E126, 2008.
[49] F. Casoli, L. Nasi, F. Albertini, S. Fabbrici, C. Bocchi, F. Ger- mini, P. Luches, A. Rota, and S. Valeri, “Morphology evolution and magnetic properties improvement in FePt epitaxial films by in situ annealing after growth,” Journal of Applied Physics, vol. 103, no. 4, p. 043912, 2008.
[50] D. Goll and A. Breitling, “Coercivity of ledge-type L10- FePt/Fe nanocomposites with perpendicular magnetization,” Ap- plied Physics Letters, vol. 94, no. 5, p. 052502, 2009.
[51] Y.-C. Wu, L.-W. Wang, and C.-H. Lai, “(001) FePt nanoparticles with ultrahigh density of 10 Tdots/in2 on amorphous SiO2 sub- strates,” Applied Physics Letters, vol. 93, no. 24, p. 242501, 2008.
[52] F. Casoli, F. Albertini, L. Nasi, S. Fabbrici, R. Cabassi, F. Bol- zoni, and C. Bocchi, “Strong coercivity reduction in perpendicular FePt/Fe bilayers due to hard/soft coupling,” Applied Physics Let- ters, vol. 92, no. 14, p. 142506, 2008.
[53] R. Saxena, M. J. Frederick, G. Ramanath, W. N. Gill, and J. L. Plawsky, “Kinetics of voiding and agglomeration of copper nanolay- ers on silica,” Physical Review B, vol. 72, p. 115425, Sep 2005.
[54] O. Nakamura, E. E. Fullerton, J. Guimpel, and I. K. Schuller, “High Tc thin films with roughness smaller than one unit cell,” Applied Physics Letters, vol. 60, no. 1, p. 120, 1992.
[55] B. D. Cullity and S. R. Stock, Elements of X-ray diffraction. Pren- tice Hall, 2001, p. 526.
[56] H. Galinski, T. Ryll, P. Elser, J. L. M. Rupp, A. Bieberle-Hu ̈tter, and L. J. Gauckler, “Agglomeration of Pt thin films on dielectric substrates,” Physical Review B, vol. 82, p. 235415, Dec 2010.
[57] S. J. A. Figueroa, S. J. Stewart, T. Rueda, A. Hernando, and P. de la Presa, “Thermal evolution of Pt-rich FePt/Fe3O4 heterodimers studied using x-ray absorption near-edge spectroscopy,” The Journal of Physical Chemistry C, vol. 115, no. 13, pp. 5500– 5508, 2011.
[58] P. D. Kirsch and J. G. Ekerdt, “Chemical and thermal reduction of thin films of copper (ii) oxide and copper (i) oxide,” Journal of Applied Physics, vol. 90, no. 8, pp. 4256–4264, 2001.
[59] W.-C. Wen, R. V. Chepulskii, L.-W. Wang, S. Curtarolo, and C.-H. Lai, “Accelerating disorder–order transitions of FePt by preforming a metastable AgPt phase,” Acta Materialia, vol. 60, no. 20, pp. 7258 – 7264, 2012.
[60] F. R. N. Nabarro, Report of a Conference on Strength of Solids. The Physical Society, 1948, p. 75.
[61] C. Herring, “Diffusional viscosity of a polycrystalline solid,” Journal of Applied Physics, vol. 21, no. 5, pp. 437–445, 1950.
[62] S. N. Hsiao, S. H. Liu, S. K. Chen, T. S. Chin, and H. Y. Lee, “Direct evidence for stress-induced (001) anisotropy of rapid-annealed FePt thin films,” Applied Physics Letters, vol. 100, no. 26, p. 261909, 2012.
[63] J. M. Shaw, S. E. Russek, T. Thomson, M. J. Donahue, B. D. Terris, O. Hellwig, E. Dobisz, and M. L. Schneider, “Reversal mechanisms in perpendicularly magnetized nanostructures,” Physical Review B, vol. 78, p. 024414, Jul 2008.
[64] J. Lee, C. Brombacher, J. Fidler, B. Dymerska, D. Suess, and M. Al- brecht, “Contribution of the easy axis orientation, anisotropy dis- tribution and dot size on the switching field distribution of bit patterned media,” Applied Physics Letters, vol. 99, no. 6, p. 062505, 2011.
[65] I. Tudosa, M. V. Lubarda, K. T. Chan, M. A. Escobar, V. Lomakin, and E. E. Fullerton, “Thermal stability of patterned Co/Pd nanodot arrays,” Applied Physics Letters, vol. 100, p. 102401, Mar 2012.
[66] Z. Yan, S. Takahashi, T. Hasegawa, S. Ishio, Y. Kondo, J. Ariake, and D. Xue, “Understanding magnetic properties of arrays of small FePt dots with perpendicular anisotropy,” Journal of Magnetism and Magnetic Materials, vol. 324, no. 22, pp. 3737 – 3740, 2012.
[67] A. Kikitsu, T. Maeda, H. Hieda, R. Yamamoto, N. Kihara, and Y. Kamata, “5 Tdots/in2 bit patterned media fabricated by a directed self-assembly mask,” IEEE Transactions on Magnetics, vol. 49, no. 2, pp. 693–698, 2013.
[68] O. Hellwig, A. Berger, T. Thomson, E. Dobisz, Z. Z. Bandic, H. Yang, D. S. Kercher, and E. E. Fullerton, “Separating dipolar broadening from the intrinsic switching field distribution in perpen- dicular patterned media,” Applied Physics Letters, vol. 90, no. 16, p. 162516, 2007.
[69] T. Thomson, G. Hu, and B. D. Terris, “Intrinsic distribution of mag- netic anisotropy in thin films probed by patterned nanostructures,” Physical Review Letters, vol. 96, p. 257204, Jun 2006.
[70] J. B. C. Engelen, M. Delalande, A. J. le F ́ebre, T. Bolhuis, T. Shi- matsu, N. Kikuchi, L. Abelmann, and J. C. Lodder, “Thermally induced switching field distribution of a single CoPt dot in a large array,” Nanotechnology, vol. 21, no. 3, p. 035703, 2010.
[71] L. Breth, D. Suess, C. Vogler, B. Bergmair, M. Fuger, R. Heer, and H. Brueckl, “Thermal switching field distribution of a single domain particle for field-dependent attempt frequency,” Journal of Applied Physics, vol. 112, no. 2, p. 023903, 2012.
[72] O. Hovorka, J. Pressesky, G. Ju, A. Berger, and R. W. Chantrell, “Distribution of switching fields in magnetic granular materials,” Applied Physics Letters, vol. 101, no. 18, p. 182405, 2012.
[73] J. W. Lau, X. Liu, R. C. Boling, and J. M. Shaw, “Decoupling nucleation and domain-wall propagation regimes in (Co/Pd)n mul- tilayer nanostructures,” Physical Review B, vol. 84, p. 214427, Dec 2011.
[74] D. Vokoun, M. Beleggia, M. D. Graef, H. C. Hou, and C. H. Lai, “The influence of magnetostatic interactions in exchange-coupled composite particles,” Journal of Physics D: Applied Physics, vol. 43, no. 27, p. 275001, 2010.
[75] J.-P. Adam, S. Rohart, J.-P. Jamet, J. Ferr ́e, A. Mougin, R. Weil, H. Bernas, and G. Faini, “Magnetization reversal by confined droplet growth in soft/hard hybrid nanodisks with perpendicular anisotropy,” Physical Review B, vol. 85, p. 214417, Jun 2012.
[76] F. Garcia-Sanchez, O. Chubykalo-Fesenko, O. Mryasov, R. W. Chantrell, and K. Y. Guslienko, “Exchange spring structures and coercivity reduction in FePt/FeRh bilayers: A comparison of mul- tiscale and micromagnetic calculations,” Applied Physics Letters, vol. 87, no. 12, p. 122501, 2005.
[77] J. Barker, R. F. L. Evans, R. W. Chantrell, D. Hinzke, and U. Nowak, “Atomistic spin model simulation of magnetic reversal modes near the Curie point,” Applied Physics Letters, vol. 97, no. 19, p. 192504, 2010.
[78] S. Okamoto, N. Kikuchi, O. Kitakami, T. Miyazaki, Y. Shimada, and K. Fukamichi, “Chemical-order-dependent magnetic anisotropy and exchange stiffness constant of FePt (001) epitaxial films,” Phys- ical Review B, vol. 66, p. 024413, Jul 2002.
[79] E. D. Boerner, O. Chubykalo-Fesenko, O. Mryasov, R. W. Chantrell, and O. Heinonen, “Moving toward an atomistic reader model,” IEEE Transactions on Magnetics, vol. 41, pp. 936–940, Feb 2005.
[80] W. F. Brown, “Thermal fluctuations of a single-domain particle,” Physical Review, vol. 130, pp. 1677–1686, Jun 1963.
[81] U. Nowak, Annual Reviews of Computational Physics IX. World Scientific, 2001, p. 105.
[82] H. L. Richards, S. W. Sides, M. Novotny, and P. A. Rikvold, “Mag- netization switching in nanoscale ferromagnetic grains: description by a kinetic Ising model,” Journal of Magnetism and Magnetic Ma- terials, vol. 150, no. 1, pp. 37 – 50, 1995.
[83] H. L. Richards, M. Kolesik, P.-A. Lindg ̊ard, P. A. Rikvold, and M. A. Novotny, “Effects of boundary conditions on magnetization switching in kinetic ising models of nanoscale ferromagnets,” Phys- ical Review B, vol. 55, pp. 11 521–11 540, May 1997.
[84] D. Hinzke and U. Nowak, “Magnetization switching in a Heisenberg model for small ferromagnetic particles,” Physical Review B, vol. 58, pp. 265–272, Jul 1998.
[85] K. Y. Guslienko, O. Chubykalo-Fesenko, O. Mryasov, R. Chantrell, and D. Weller, “Magnetization reversal via perpendicular exchange spring in FePt/FeRh bilayer films,” Physical Review B, vol. 70, p. 104405, Sep 2004.
[86] H. Kronmu ̈ller and D. Goll, “Micromagnetic theory of the pinning of domain walls at phase boundaries,” Physica B, vol. 319, pp. 122 – 126, 2002.
[87] D. Suess, “Multilayer exchange spring media for magnetic record- ing,” Applied Physics Letters, vol. 89, no. 11, p. 113105, 2006.
[88] H. Callen and E. Callen, “The present status of the temperature dependence of magnetocrystalline anisotropy, and the l(l+1)2 power law,” Journal of Physics and Chemistry of Solids, vol. 27, no. 8, pp. 1271 – 1285, 1966.
[89] P. Asselin, R. F. L. Evans, J. Barker, R. W. Chantrell, R. Yanes, O. Chubykalo-Fesenko, D. Hinzke, and U. Nowak, “Constrained monte carlo method and calculation of the temperature dependence of magnetic anisotropy,” Physical Review B, vol. 82, p. 054415, Aug 2010.
[90] F. Heider and W. Williams, “Note on temperature dependence of exchange constant in magnetite,” Geophysical Research Letters, vol. 15, no. 2, pp. 184–187, 1988.
[91] U. Atxitia, D. Hinzke, O. Chubykalo-Fesenko, U. Nowak, H. Kachkachi, O. N. Mryasov, R. F. Evans, and R. W. Chantrell, “Multiscale modeling of magnetic materials: Temperature depen- dence of the exchange stiffness,” Physical Review B, vol. 82, p. 134440, Oct 2010.
[92] P. Gaunt, “Magnetic viscosity and thermal activation energy,” Jour- nal of Applied Physics, vol. 59, no. 12, pp. 4129–4132, 1986.
[93] H. J. Richter and A. Y. Dobin, “Analysis of magnetization processes in composite media grains,” Journal of Applied Physics, vol. 99, no. 8, p. 08Q905, 2006.
[94] J.-P. Wang, W. K. Shen, J. M. Bai, R. H. Victora, J. H. Judy, and W. L. Song, “Composite media (dynamic tilted media) for magnetic recording,” Applied Physics Letters, vol. 86, no. 14, p. 142504, 2005.
[95] P. Langevin, “Magn ́etism et th ́eorie des electrons,” Annnales de Chemie et de Physique, vol. 5, pp. 70–127, 1905.
[96] J. Crangle and G. M. Goodman, “The magnetization of pure iron and nickel,” Proceedings of the Royal Society of London A, vol. 321, no. 1547, pp. 477–491, 1971.
[97] D. A. Gilbert, L.-W. Wang, T. J. Klemmer, J.-U. Thiele, C.-H. Lai, and K. Liu, “Tuning magnetic anisotropy in (001) oriented L10 (Fe1−xCux)55Pt45 films,” Applied Physics Letters, vol. 102, no. 13, p. 132406, 2013.
[98] T. Seki, K. Utsumiya, Y. Nozaki, H. Imamura, and K. Takanashi, “Spin wave-assisted reduction in switching field of highly coercive iron-platinum magnets,” Nature Communications, vol. 4, p. 1726, 2013.
[99] J. E. Davies, O. Hellwig, E. E. Fullerton, G. Denbeaux, J. B. Ko- rtright, and K. Liu, “Magnetization reversal of Co/Pt multilayers: Microscopic origin of high−field magnetic irreversibility,” Physical Review B, vol. 70, p. 224434, Dec 2004.
[100] B. J. Kirby, J. E. Davies, K. Liu, S. M. Watson, G. T. Zimanyi, R. D. Shull, P. A. Kienzle, and J. A. Borchers, “Vertically graded anisotropy in Co/Pd multilayers,” Physical Review B, vol. 81, p. 100405, Mar 2010.
[101] B. Cullity and C. Graham, Introduction to Magnetic Materials. Wiley, 2009.

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