E-mail Alert
RSS
| Citation: |
|
Direct laser interference patterning of nonvolatile magnetic nanostructures in Fe60Al40 alloy via disorder-induced ferromagnetism
-
Abstract
Current magnetic memories are based on writing and reading out the domains with opposite orientation of the magnetization vector. Alternatively, information can be encoded in regions with a different value of the saturation magnetization. The latter approach can be realized in principle with chemical order-disorder transitions in intermetallic alloys. Here, we study such transformations in a thin-film (35 nm) Fe60Al40alloy and demonstrate the formation of periodic magnetic nanostructures (PMNS) on its surface by direct laser interference patterning (DLIP). These PMNS are nonvolatile and detectable by magnetic force microscopy (MFM) at room temperature after DLIP with a single nanosecond pulse. We provide different arguments that the PMNS we observe originate from increasing magnetization in maxima of the interference pattern because of chemical disordering in the atomic lattice of the alloy at temperatures T higher than the critical temperature Tc for the order (B2)-disorder (A2) transition. Theoretically, our simulations of the temporal evolution of a partially ordered state at T > Tc reveal that the disordering rate is significant even below the melting threshold. Experimentally, we find that the PMNS are erasable with standard thermal annealing at T < Tc.-
Keywords:
- thin films /
- laser patterning /
- magnetic dots /
- magnetic memory
-
-
References
[1] Nix F C, Shockley W. Order-disorder transformations in alloys. Rev Mod Phys 10, 1-71 (1938). doi: 10.1103/RevModPhys.10.1 [2] Cook H E, de Fontaine D, Hilliard J E. A model for diffusion on cubic lattices and its application to the early stages of ordering. Acta Metall 17, 765-773 (1969). doi: 10.1016/0001-6160(69)90083-2 [3] Metiu H, Kitahara K, Ross J. Stochastic theory of the kinetics of phase transitions. J Chem Phys 64, 292-299 (1976). doi: 10.1063/1.431920 [4] Khachaturyan A G. Ordering in substitutional and interstitial solid solutions. Prog Mater Sci 22, 1-150 (1978). doi: 10.1016/0079-6425(78)90003-8 [5] Martin G. Relaxation rate of conserved and nonconserved order parameters in replacive transitions. Phys Rev B 50, 12362-12366 (1994). doi: 10.1103/PhysRevB.50.12362 [6] Ye J, Bellon P. Nanoscale patterning of chemical order induced by displacement cascades in irradiated alloys. I. A kinetic Monte Carlo study. Phys Rev B 70, 094104 (2004). doi: 10.1103/PhysRevB.70.094104 [7] Mehrer H, Eggersmann M, Gude A, Salamon M, Sepiol B. Diffusion in intermetallic phases of the Fe-Al and Fe-Si Systems. Mater Sci Eng: A 239-240, 889-898 (1997). doi: 10.1016/S0921-5093(97)00680-1 [8] Eggersmann M, Mehrer H. Diffusion in intermetallic phases of the Fe-Al system. Philos Mag A 80, 1219-1244 (2000). doi: 10.1080/13642810008208592 [9] Würschum R, Grupp C, Schaefer H E. Simultaneous study of vacancy formation and migration at high temperatures in B2-type Fe aluminides. Phys Rev Lett 75, 97-100 (1995). doi: 10.1103/PhysRevLett.75.97 [10] Stana M, Sepiol B, Kozubski R, Leitner M. Chemical ordering beyond the superstructure in long-range ordered systems. New J Phys 18, 113051(2016). doi: 10.1088/1367-2630/18/11/113051 [11] Huffman G P, Fisher R M. Mössbauer studies of ordered and cold-worked Fe-Al alloys containing 30 to 50 at. % aluminum. J Appl Phys 38, 735 (1967). doi: 10.1063/1.1709403 [12] Beck P A. Some recent results on magnetism in alloys. Metall Mater Trans B 2, 2015-2024 (1971). doi: 10.1007/BF02917527 [13] Hernando A, Amils X, Nogués J, Surinãch S, Baró M D et al. Influence of magnetization on the reordering of nanostructured ball-milled Fe-40 at. % Al powders. Phys Rev B 58, R118649(R) (1998). doi: 10.1103/PhysRevB.58.R11864 [14] Menéndez E, Sort J, Liedke M O, Fassbender J, Suriñach S et al. Two-fold origin of the deformation-induced ferromagnetism in bulk Fe60Al40 (at.%) alloys. New J Phys 10, 103030 (2008). doi: 10.1088/1367-2630/10/10/103030 [15] Zamora L E, Alcázar G A P, Vélez G Y, Betancur J D, Marco J F et al. Disorder effect on the magnetic behavior of mechanically alloyed Fe1-x Alx (0.2≤x≤0.4). Phys Rev B 79, 094418 (2009). doi: 10.1103/PhysRevB.79.094418 [16] Murakami Y, Niitsu K, Tanigaki T, Kainuma R, Park H S et al. Magnetization amplified by structural disorder within nanometre scale interface region. Nat Commun 5, 4133 (2014). doi: 10.1038/ncomms5133 [17] Bali R, Wintz S, Meutzner F, Hübner R, Boucher R et al. Printing nearly-discrete magnetic patterns using chemical disorder induced ferromagnetism. Nano Lett 14, 435-441 (2014). doi: 10.1021/nl404521c [18] Polushkin N I, Oliveira V, Vilar R, He M, Shugaev M V et al. Phase- change magnetic memory: Rewritable ferromagnetism by laser quenching of chemical disorder in Fe60Al40 alloy. Phys Rev Appl 10, 024023 (2018). doi: 10.1103/PhysRevApplied.10.024023 [19] Yoshida Y, Oosawa K, Watanabe S, Kaiju H, Kondo K et al. Nanopatterns induced by pulsed laser irradiation on the surface of an Fe-Al alloy and their magnetic properties. Appl Phys Lett 102, 183109 (2013). doi: 10.1063/1.4804363 [20] Ehrler J, He M, Shugaev M V, Polushkin N I, Wintz S et al. Laser-rewriteable ferromagnetism at thin-film surfaces. ACS Appl Mater Interfaces 10, 15232-15239 (2018). doi: 10.1021/acsami.8b01190 [21] Apiñaniz E, Plazaola F, Garitaonandia J S. Electronic structure calculations of Fe-rich ordered and disordered Fe-Al alloys. Eur Phys J B 31, 167-177 (2003). doi: 10.1140/epjb/e2003-00021-y [22] Plazaola F, Apiñaniz E, Rodriguez D M, Legarra E, Garitaonandia J S. Fe-Al alloys' magnetism. In Advanced Magnetic Materials, Ed. by Malkinski L, University of New Orleans, USA, 2002. [23] Kulikov N I, Postnikov A V, Borstel G, Braun J. Onset of magnetism in B 2 transition-metal aluminides. Phys Rev B 59, 6824-6833 (1999). doi: 10.1103/PhysRevB.59.6824 [24] Smirnov A V, Shelton W A, Johnson D D. Importance of thermal disorder on the properties of alloys: origin of paramagnetism and structural anomalies in bcc-based Fe1-xAlx. Phys Rev B 71, 064408 (2005). doi: 10.1103/PhysRevB.71.064408 [25] Palm M, Stein F, Dehm G. Iron aluminides. Annu Rev Mater Res 49, 297-326 (2019). doi: 10.1146/annurev-matsci-070218-125911 [26] Müller-Meskamp L, Kim Y H, Roch T, Hofmann S, Scholz R et al. Efficiency enhancement of organic solar cells by fabricating periodic surface textures using direct laser interference patterning. Adv Mater 24, 906-910 (2012). doi: 10.1002/adma.201104331 [27] Daniel C, Mücklich F, Liu Z. Periodical micro-nano-structuring of metallic surfaces by interfering laser beams. Appl Surf Sci 208-209, 317-321 (2003). doi: 10.1016/S0169-4332(02)01381-8 [28] Zheng M, Yu M, Liu Y, Skomski R, Liou S H et al. Magnetic nanodot arrays produced by direct laser interference lithography. Appl Phys Lett 79, 2606-2608 (2001). doi: 10.1063/1.1409948 [29] Stärk M, Schlickeiser F, Nissen D, Hebler B, Graus P et al. Controlling the magnetic structure of Co/Pd thin films by direct laser interference patterning. Nanotechnology 26, 205302 (2015). doi: 10.1088/0957-4484/26/20/205302 [30] Martín-Fabiani I, Riedel S, Rueda D R, Siegel J, Boneberg J et al. Micro- and submicrostructuring thin polymer films with two and three-beam single pulse laser interference lithography. Langmuir 30, 8973-8979 (2014). doi: 10.1021/la5021059 [31] Davies C S, Januŝonis J, Kimel A V, Kirilyuk A, Tsukamoto A et al. Towards massively parallelized all-optical magnetic recording. J Appl Phys 123, 213904 (2018). doi: 10.1063/1.5003713 [32] Timmerwilke J, Liou S H, Cheng S F, Edelstein A S, Rewriting magnetic phase change memory by laser heating. J Phys D: Appl Phys 49, 165005 (2016). doi: 10.1088/0022-3727/49/16/165005 [33] Wang D P, Wang Z B, Zhang Z A, Yue Y, Li D Y et al. Effects of polarization on four-beam laser interference lithography. Appl Phys Lett 102, 081903 (2013). doi: 10.1063/1.4793752 [34] Bischof J. Metallische dünnfilmschmelzen nach pulslaser-bestrahlung: phasenumwandlungen und Instabilitäten (Konstanz, Univ, Diss, 1997). [35] Rudajevová A, Buriánek J. Determination of thermal diffusivity and thermal conductivity of Fe-Al Alloys in the concentration range 22 to 50 at.% Al. J Phase Equilib 22, 560-563 (2001). doi: 10.1007/s11669-001-0075-1 [36] Chanbi D, Ogam E, Amara S E, Fellah Z E A. Synthesis and mechanical characterization of binary and ternary intermetallic alloys based on Fe-Ti-Al by resonant ultrasound vibrational methods. Materials 11, 746 (2018). doi: 10.3390/ma11050746 [37] Piatkowski J, Przeliorz R, Jablonska M. The specific heat capacity and oxidation kinetics of NiAl, FeAl and TiAl alloys. Solid State Phenom 203-204, 431-434 (2013). doi: 10.4028/www.scientific.net/SSP.203-204.431 [38] Bukharaev A A, Ovchinnikov D V, Nurgazizov N I, Kukovitskiĭ E F, Klaĭber M et al. Investigation of micromagnetism and magnetic reversal of Ni nanoparticles using a magnetic force microscope. Phys Solid State 40, 1163-1168 (1998). doi: 10.1134/1.1130511 [39] Alekseev A M, Bykov V A, Popkov A F, Polushkin N I, Korneev V I. Observation of remanent states of small magnetic particles: Micromagnetic simulation and experiment. J Exp Theor Phys Lett 75, 268-272 (2002). doi: 10.1134/1.1481461 [40] Zhu X B, Grutter P. Magnetic force microscopy studies of patterned magnetic structures. IEEE Trans Magn 39, 3420-3425 (2003). doi: 10.1109/TMAG.2003.816170 [41] Zhang W, Singh R, Bray-Ali N, Haas S. Scaling analysis and application: phase diagram of magnetic nanorings and elliptical nanoparticles. Phys Rev B 77, 144428 (2008). doi: 10.1103/PhysRevB.77.144428 [42] Chang J, Mironov V L, Gribkov B A, Fraerman A A, Gusev S A et al. Magnetic state control of ferromagnetic nanodots by magnetic force microscopy probe. J Appl Phys 100, 104304 (2006). doi: 10.1063/1.2384811 [43] Wei J S, Jiao X B, Gan F X, Xiao M F. Laser pulse induced bumps in chalcogenide phase change films. J Appl Phys 103, 124516 (2008). doi: 10.1063/1.2948928 [44] Stein F, Palm M. Re-determination of transition temperatures in the Fe-Al system by differential thermal analysis. Int J Mater Res 98, 580-588 (2007). doi: 10.3139/146.101512 -
Supplementary Information
Supplementary information for Direct laser interference patterning of nonvolatile magnetic nanostructures in Fe60Al40 alloy via disorder-induced ferromagnetism 
-
Access History
Figures(6)
Article Metrics
Export File
Citation
Format
Content
DownLoad:
-
Figure 1.
(a) Schematic of the DLIP geometry with four laser beams that impinge on the sample surface and their superposition provides the interference pattern. (b) Laser intensity distribution simulated for all the beams of TE polarization and equal intensity, which incident at the same angle θ, while the azimuthal angles are φi=π(i-1)/2, where i=1, 2, 3, 4. Under such parameters, the lattice periodicity is given by Λ=λ/(2sinθ)33. In our experiments, Λ was varied between 0.4 and 2.3 µm. (c) MFM image of a Fe60Al40 35 nm thick sample treated by DLIP with Λ=0.4 μm and (d) corresponding topography.
-
Figure 2.
MFM images of patterned structures that have different periodicities Λ of the interference pattern. (a) 0.4 μm, (b), 0.6 μm, and (c) 2.3 μm.
-
Figure 3.
Correspondence between the laser-induced topographical relief (a) and MFM response (b). The bumps on the Fe60Al40 surface, occurring within maxima of light intensity (solid contours), are significantly smaller in their lateral dimensions than the regions in which the MFM response is nonzero. One of the patterned magnetic entities is indicated by dashed contour.
-
Figure 4.
(a) Fe-based unit cells (top) and the (100) projections (bottom) of the atomic structure in the chemically ordered B2 and disordered A2 states of the FexAl100-x (x~50 at.%) alloy. The open boxes are vacancies in the lattice through which the atomic jumps occur for relaxation of the system to its thermodynamic equilibrium. In the A2 state there are magnetic percolation paths (dashed lines). (b) Simulated change of magnetic moments in Fe under the transformation from the B2 to A2 state21.
-
Figure 5.
(a) Absorbed fluence Fabs as a function of coordinate along the dashed horizontal line in Fig. 1(b) with indications of different positions: 1. maxima of light intensity, where Fabs=(1–R)F*>Fm (Fm is the absorbed fluence required for raising the temperature up to the melting point Tm); 2. locations outside the melted zones, in which Fc < Fabs < Fm (Fc is the absorbed fluence required for raising the temperature up to Tc); 3. local minima of light intensity. (b) T(t) dependencies calculated in positions 1, 2, and 3, where the absorbed fluence is respectively Fabs=70 mJ/cm2, Fabs=65 mJ/cm2, and Fabs=35 mJ/cm2. As temperature elevation was calculated with no taking into account effects of melting and resolidification18, 20, the T(t) dependence calculated at Fabs>Fm is shown by the dashed curve for t>tm, where tm is the moment of time at which the temperature rise reaches Tm. (c) Unit cell of the interference pattern with the marks for positions in which the T(t) dependences plotted in (b) are simulated. (d) Non-equilibrium vacancy concentration cv versus t in zone(s) 2 at Tmax=Tm. The inset shows the asymptotic value cv(∞) at different temperature elevations Tmax-Tc up to Tmax=Tm. (e) Concentration wave (superstructure) amplitude A(t)/A(0) as a function of time t in zone(s) 2 at different temperature elevations Tmax-Tc up to Tmax=Tm.
-
Figure 6.
MFM images of the patterned Fe60Al40 surface at the edge of the irradiated zone. The images were taken (a) before and (b) after thermal annealing in a furnace at T=770 K for one hour. (c) Cross section of the MFM image before and after thermal annealing
