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Room-temperature antiferromagnetic memory resistor

Nature Materials volume 13, pages 367–374 (2014)Cite this article

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Abstract

The bistability of ordered spin states in ferromagnets provides the basis for magnetic memory functionality. The latest generation of magnetic random access memories rely on an efficient approach in which magnetic fields are replaced by electrical means for writing and reading the information in ferromagnets. This concept may eventually reduce the sensitivity of ferromagnets to magnetic field perturbations to being a weakness for data retention and the ferromagnetic stray fields to an obstacle for high-density memory integration. Here we report a room-temperature bistable antiferromagnetic (AFM) memory that produces negligible stray fields and is insensitive to strong magnetic fields. We use a resistor made of a FeRh AFM, which orders ferromagnetically roughly 100 K above room temperature, and therefore allows us to set different collective directions for the Fe moments by applied magnetic field. On cooling to room temperature, AFM order sets in with the direction of the AFM moments predetermined by the field and moment direction in the high-temperature ferromagnetic state. For electrical reading, we use an AFM analogue of the anisotropic magnetoresistance. Our microscopic theory modelling confirms that this archetypical spintronic effect, discovered more than 150 years ago in ferromagnets, is also present in AFMs. Our work demonstrates the feasibility of fabricating room-temperature spintronic memories with AFMs, which in turn expands the base of available magnetic materials for devices with properties that cannot be achieved with ferromagnets.

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Figure 1: AFM-AMR memory functionality in a FeRh resistor.
Figure 2: Characterization of the magnetic and crystal structure of the FeRh film.
Figure 3: Magnetic properties.
Figure 4: Stability of the memory states at high magnetic fields.
Figure 5: Temperature dependence of the AMR.

References

  1. Umetsu, R. Y., Sakuma, A. & Fukamichi, K. Magnetic anisotropy energy of antiferromagnetic L10-type equiatomic Mn alloys. Appl. Phys. Lett. 89, 052504 (2006).

    Article  Google Scholar 

  2. Szunyogh, L., Lazarovits, B., Udvardi, L., Jackson, J. & Nowak, U. Giant magnetic anisotropy of the bulk antiferromagnets IrMn and IrMn3 from first principles. Phys. Rev. B 79, 020403 (2009).

    Article  Google Scholar 

  3. Thomson, W. On the electro-dynamic qualities of metals: Effects of magnetization on the electric conductivity of nickel and of iron. Proc. R. Soc. Lond. 8, 546–550 (1857).

    Article  Google Scholar 

  4. McGuire, T. & Potter, R. Anisotropic magnetoresistance in ferromagnetic 3d alloys. IEEE Trans. Magn. 11, 1018–1038 (1975).

    Article  Google Scholar 

  5. Shick, A. B., Khmelevskyi, S., Mryasov, O. N., Wunderlich, J. & Jungwirth, T. Spin-orbit coupling induced anisotropy effects in bimetallic antiferromagnets: A route towards antiferro-magnetic spintronics. Phys. Rev. B 81, 212409 (2010).

    Article  Google Scholar 

  6. Park, B. G. et al. A spin-valve-like magnetoresistance of an antiferromagnet-based tunnel junction. Nature Mater. 10, 347–351 (2011).

    Article  CAS  Google Scholar 

  7. Duine, R. Spintronics: An alternating alternative. Nature Mater. 10, 345 (2011).

    Article  Google Scholar 

  8. Marti, X. et al. Electrical measurement of antiferromagnetic moments in exchange-coupled IrMn/NiFe stacks. Phys. Rev. Lett. 108, 017201 (2012).

    Article  CAS  Google Scholar 

  9. Wang, Y. Y. et al. Room-temperature perpendicular exchange coupling and tunneling anisotropic magnetoresistance in an antiferromagnet-based tunnel junction. Phys. Rev. Lett. 109, 137201 (2012).

    Article  CAS  Google Scholar 

  10. Petti, D. et al. Storing magnetic information in IrMn/MgO/Ta tunnel junctions via field-cooling. Appl. Phys. Lett. 102, 192404 (2013).

    Article  Google Scholar 

  11. Marder, M. P. Condensed Matter Physics (Wiley, (2000).

    Google Scholar 

  12. Loth, S., Baumann, S., Lutz, C. P., Eigler, D. M. & Heinrich, A. J. Bistability in atomic-scale antiferromagnets. Science 335, 196–199 (2012).

    Article  CAS  Google Scholar 

  13. Shirane, G., Chen, C. W., Flinn, P. A. & Nathans, R. Mossbauer study of hyperfine fields and isomer shifts in the Fe–Rh alloys. Phys. Rev. 131, 183–190 (1963).

    Article  CAS  Google Scholar 

  14. Sharma, M. et al. Magnetotransport properties of epitaxial MgO(001)/FeRh films across the antiferromagnet to ferromagnet transition. J. Appl. Phys. 109, 083913 (2011).

    Article  Google Scholar 

  15. Mariager, S. O., Guyader, L. L., Buzzi, M., Ingold, G. & Quitmann, C. Imaging the antiferro-magnetic to ferromagnetic first order phase transition of FeRh. Preprint at http://arxiv.org/abs/1301.4164

  16. Banhart, J. & Ebert, H. First-principles theory of spontaneous-resistance anisotropy and spontaneous Hall effect in disordered ferromagnetic alloys. Europhys. Lett. 32, 517–522 (1995).

    Article  CAS  Google Scholar 

  17. Ebert, H., Vernes, A. & Banhart, J. Anisotropic electrical resistivity of ferromagnetic Co–Pd and Co–Pt alloys. Phys. Rev. B 54, 8479–8486 (1996).

    Article  CAS  Google Scholar 

  18. Vernes, A, Ebert, H. & Banhart, J. Electronic conductivity in NiCr and NiCu fcc alloy systems. Phys. Rev. B 68, 134404 (2003).

    Article  Google Scholar 

  19. Turek, I. & Zalezak, T. Residual resistivity and its anisotropy in random CoNi and CuNi ferromagnetic alloys. J. Phys. Conf. Ser. 200, 052029 (2010).

    Article  Google Scholar 

  20. Turek, I., Kudrnovský, J. & Drchal, V. Ab initio theory of galvanomagnetic phenomena in ferromagnetic metals and disordered alloys. Phys. Rev. B 86, 014405 (2012).

    Article  Google Scholar 

  21. Gould, C. et al. Tunneling anisotropic magnetoresistance: A spin-valve like tunnel magnetoresistance using a single magnetic layer. Phys. Rev. Lett. 93, 117203 (2004).

    Article  CAS  Google Scholar 

  22. Brey, L., Tejedor, C. & Fernández-Rossier, J. Tunnel magneto-resistance in GaMnAs: Going beyond Jullière formula. Appl. Phys. Lett. 85, 1996–1998 (2004).

    Article  CAS  Google Scholar 

  23. Shick, A. B., Máca, F., Mašek, J. & Jungwirth, T. Prospect for room temperature tunnelling anisotropic magnetoresistance effect: Density of states anisotropies in CoPt systems. Phys. Rev. B 73, 024418 (2006).

    Article  Google Scholar 

  24. Gao, L. et al. Bias voltage dependence of tunneling anisotropic magnetoresistance in magnetic tunnel junctions with MgO and Al2O3 tunnel barriers. Phys. Rev. Lett. 99, 226602 (2007).

    Article  Google Scholar 

  25. Moser, J. et al. Tunneling anisotropic magnetoresistance and spin–orbit coupling in Fe/GaAs/Au tunnel junctions. Phys. Rev. Lett. 100, 056601 (2007).

    Article  Google Scholar 

  26. Park, B. G. et al. Tunneling anisotropic magnetoresistance in multilayer-(Co/Pt)/AlO x /Pt structures. Phys. Rev. Lett. 100, 087204 (2008).

    Article  CAS  Google Scholar 

  27. Marti, X. et al. Anisotropic magnetoresistance in antiferromagnetic semiconductor Sr2IrO4 epitaxial heterostructure. Preprint at http://arxiv.org/abs/1303.4704

  28. Rushforth, A. W. et al. Anisotropic magnetoresistance components in (Ga,Mn)As. Phys. Rev. Lett. 99, 147207 (2007).

    Article  CAS  Google Scholar 

  29. Stöhr, J., Padmore, H. A., Anders, S., Stammler, T. & Sheinfein, M. R. Principles of X-ray magnetic dichroism spectromiscroscopy. Surf. Rev. Lett. 5, 1297–1308 (1998).

    Article  Google Scholar 

  30. Kuneš, J. & Oppeneer, P. M. Anisotropic x-ray magnetic linear dichroism at the L edges of cubic Fe, Co, and Ni: Ab initio calculations and model theory. Phys. Rev. B 67, 024431 (2003).

    Article  Google Scholar 

  31. Chappert, C., Fert, A. & Dau, F. N. V. The emergence of spin electronics in data storage. Nature Mater. 6, 813–823 (2007).

    Article  CAS  Google Scholar 

  32. Miron, I. M. et al. Perpendicular switching of a single ferromagnetic layer induced by in-plane current injection. Nature 476, 189 (2011).

    Article  CAS  Google Scholar 

  33. Liu, L. et al. Spin-torque switching with the giant spin hall effect of tantalum. Science 336, 555–558 (2012).

    Article  CAS  Google Scholar 

  34. Kurebayashi, H. et al. Observation of a Berry phase anti-damping spin-orbit torque. Preprint at http://arxiv.org/abs/1306.1893

  35. Kimel, A. V., Kirilyuk, A., Tsvetkov, A., Pisarev, R. V. & Rasing, Th. Laser-induced ultrafast spin reorientation in the antiferromagnet TmFeO3 . Nature 429, 850–853 (2004).

    Article  CAS  Google Scholar 

Download references

Acknowledgements

The authors acknowledge the support from the NSF (Nanosystems Engineering Research Center for Translational Applications of Nanoscale Multiferroic Systems, Cooperative Agreement Award EEC-1160504) and DOE. Transmission electron microscopy characterization was performed at NCEM, which is supported by the Office of Science, Office of Basic Energy Sciences of the US Department of Energy under Contract No. DE-AC02—05CH11231. J.F. acknowledges financial support from the Spanish Government (Projects MAT2011-29269-C03, CSD2007-00041) and Generalitat de Catalunya (2009 SGR 00376); C.F. acknowledges financial support from the Spanish Government (Projects MAT2012-33207, CSD2007-00041). I.F. acknowledges a Beatriu de Pinós postdoctoral scholarship (2011 BP-A 00220) and the Catalan Agency for Management of University and Research Grants (AGAUR-Generalitat de Catalunya). X.M. acknowledges the Grant Agency of the Czech Republic No. P204/11/P339. Research at the University of Nottingham was funded by EPSRC grant EP/K027808/1. T.J. acknowledges support from the ERC Advanced Grant 268066, Praemium Academiae of the Academy of Sciences of the Czech Republic, and from the Ministry of Education of the Czech Republic Grant LM2011026. S.S. acknowledges funding by STARnet FAME. J. Kuneš 83 and I.T. acknowledge the Czech Science Foundation No. P204/11/1228.

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Authors and Affiliations

  1. Department of Materials Science and Engineering and Department of Physics, University of California, Berkeley, California 94720, USA

    X. Marti, R. J. Paull, J. D. Clarkson & R. Ramesh

  2. Department of Condensed Matter Physics, Faculty of Mathematics and Physics, Charles University, 12116 Praha 2, Czech Republic

    X. Marti & I. Turek

  3. Institute of Physics ASCR, v.v.i., Cukrovarnická 10, 162 53 Praha 6, Czech Republic,

    X. Marti, P. Wadley, J. Kuneš & T. Jungwirth

  4. Institut de Ciència de Materials de Barcelona, ICMAB-CSIC, Campus UAB, Bellaterra E-08193, Spain

    I. Fina, C. Frontera & J. Fontcuberta

  5. Max Planck Institute of Microstructure Physics, Weinberg 2, Halle D-06120, Germany,

    I. Fina

  6. Materials Science Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA

    Jian Liu, D. Yi, J-H. Chu & R. Ramesh

  7. School of Physics and Astronomy, University of Nottingham, Nottingham NG7 2RD, UK

    P. Wadley & T. Jungwirth

  8. Advanced Light Source, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA

    Q. He & E. Arenholz

  9. Institute of Physics ASCR, v.v.i., Na Slovance 2, 182 21 Praha 8, Czech Republic,

    J. Kudrnovský

  10. Institute of Physics of Materials ASCR, v.v.i., Zizkova 22, Brno 616 62, Czech Republic,

    I. Turek

  11. National Center for Electron Microscopy, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA

    C. T. Nelson

  12. Department of Electrical Engineering and Computer Sciences, University of California, Berkeley, Berkeley, California 94720, USA

    L. You & S. Salahuddin

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  1. X. Marti
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Contributions

Sample preparation, R.J.P., J.D.C., L.Y.; scanning transmission electron microscopy, C.T.N.; magnetotransport and structural characterization, I.F. and C.F.; data analysis, I.F., C.F., P.W., J-H.C. and D.Y.; X-ray linear dichroism, J.L., E.A. and Q.H.; theory, J. Kudrnovský, I.T. and J. Kuneš; writing and project planning, X.M., T.J., J.F., P.W., S.S. and R.R.

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Correspondence to X. Marti.

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Marti, X., Fina, I., Frontera, C. et al. Room-temperature antiferromagnetic memory resistor. Nature Mater 13, 367–374 (2014). https://doi.org/10.1038/nmat3861

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