journal article·2019-12-17Open access

Magneto-ionic control of spin polarization in multiferroic tunnel junctions

Yingfen Wei, Sylvia Matzen, Cynthia P. Quinteros, Thomas Maroutian, Guillaume Agnus, Philippe Lecoeur, Beatriz Noheda

npj Quantum Materials· Volume 4· Issue 1

Abstract

Abstract Multiferroic tunnel junctions (MFTJs) with Hf0.5Zr0.5O2 barriers are reported to show both tunneling magnetoresistance effect (TMR) and tunneling electroresistance effect (TER), displaying four resistance states by magnetic and electric field switching. Here we show that, under electric field cycling of large enough magnitude, the TER can reach values as large as 106%. Moreover, concomitant with this TER enhancement, the devices develop electrical control of spin polarization, with sign reversal of the TMR effect. Currently, this intermediate state exists for a limited number of cycles and understanding the origin of these phenomena is key to improve its stability. The experiments presented here point to the magneto-ionic effect as the origin of the large TER and strong magneto-electric coupling, showing that ferroelectric polarization switching of the tunnel barrier is not the main contribution.
Source: crossref · Quality: baseline

Research context

OpenAlex topics: Ferroelectric and Negative Capacitance Devices · Advanced Memory and Neural Computing · Multiferroics and related materials

SciVX discovery tags are terminology-based. OpenAlex topics are source-provided classifications.

References (61)

Show source-provided references
1. Gajek, M. et al. Tunnel junctions with multiferroic barriers. Nat. Mater. 6, 296–302 (2007).10.1038/nmat1860 ↗
2. Rodríguez Contreras, J. et al. Resistive switching in metal-ferroelectric-metal junctions. Appl. Phys. Lett. 83, 4595 (2003).10.1063/1.1627944 ↗
3. Tsymbal, E. Y., Gruverman, A., Garcia, V., Bibes, M. & Barthélémy, A. Ferroelectric and multiferroic tunnel junctions. MRS bull. 37, 138–143 (2012).10.1557/mrs.2011.358 ↗
4. Scott, J. Multiferroic memories. Nat. Mater. 6, 256–257 (2007).10.1038/nmat1868 ↗
5. Hur, N. et al. Electric polarization reversal and memory in a multiferroic material induced by magnetic fields. Nature 429, 392–395 (2004).10.1038/nature02572 ↗
6. Bibes, M. & Barthélémy, A. Towards a magnetoelectric memory. Nat. Mater. 7, 425–426 (2008).10.1038/nmat2189 ↗
7. Ortega, N., Kumar, A., Scott, J. & Katiyar, R. S. Multifunctional magnetoelectric materials for device applications. J. Phys: Condens. Matter 27, 504002 (2015).
8. Eerenstein, W., Mathur, N. & Scott, J. F. Multiferroic and magnetoelectric materials. Nature 442, 759–765 (2006).10.1038/nature05023 ↗
9. Ramesh, R. & Spaldin, N. A. Multiferroics: progress and prospects in thin films. Nat. Mater. 6, 21–29 (2007).10.1038/nmat1805 ↗
10. Fiebig, M. Revival of the magnetoelectric effect. J. Phys. D: Appl. Phys. 38, R123 (2005).10.1088/0022-3727/38/8/R01 ↗
11. Garcia, V. et al. Ferroelectric control of spin polarization. Science 327, 1106–1110 (2010).10.1126/science.1184028 ↗
12. Yin, Y. & Li, Q. A review on all-perovskite multiferroic tunnel junctions. J Materiomics 3, 245–254 (2017).10.1016/j.jmat.2017.09.001 ↗
13. Vaz, C. A., Hoffman, J., Ahn, C. H. & Ramesh, R. Magnetoelectric coupling effects in multiferroic complex oxide composite structures. Adv. Mater. 22, 2900–2918 (2010).10.1002/adma.200904326 ↗
14. Lee, J. H. et al. A strong ferroelectric ferromagnet created by means of spin-lattice coupling. Nature 466, 954–958 (2010).10.1038/nature09331 ↗
15. Wang, K., Liu, J.-M. & Ren, Z. Multiferroicity: the coupling between magnetic and polarization orders. Adv. Phys. 58, 321–448 (2009).10.1080/00018730902920554 ↗
16. Eerenstein, W., Wiora, M., Prieto, J., Scott, J. & Mathur, N. Giant sharp and persistent converse magnetoelectric effects in multiferroic epitaxial heterostructures. Nat. Mater. 6, 348–351 (2007).10.1038/nmat1886 ↗
17. Rondinelli, J. M., Stengel, M. & Spaldin, N. A. Carrier-mediated magnetoelectricity in complex oxide heterostructures. Nat. Nanotechnol. 3, 46–50 (2008).10.1038/nnano.2007.412 ↗
18. Lu, H. et al. Electric modulation of magnetization at the BaTiO$$3$$/La$$3$$Sr$$3$$MnO$$3$$ interfaces. Appl. Phys. Lett. 100, 232904 (2012).10.1063/1.4726427 ↗
19. Vaz, C. et al. Temperature dependence of the magnetoelectric effect in Pb(Zr$$0.2$$ Ti$$0.2$$)O$$0.2$$/La$$0.2$$Sr$$0.2$$MnO$$0.2$$ multiferroic heterostructures. Appl. Phys. Lett. 97, 042506 (2010).10.1063/1.3472259 ↗
20. Dawber, M., Rabe, K. & Scott, J. Physics of thin-film ferroelectric oxides. Rev. Mod. Phys. 77, 1083 (2005).10.1103/RevModPhys.77.1083 ↗
21. Mathews, S., Ramesh, R., Venkatesan, T. & Benedetto, J. Ferroelectric field effect transistor based on epitaxial perovskite heterostructures. Science 276, 238–240 (1997).10.1126/science.276.5310.238 ↗
22. Wu, S. et al. Full electric control of exchange bias. Phys. Rev. Lett. 110, 067202 (2013).10.1103/PhysRevLett.110.067202 ↗
23. Skumryev, V. et al. Magnetization reversal by electric-field decoupling of magnetic and ferroelectric domain walls in multiferroic-based heterostructures. Phys. Rev. Lett. 106, 057206 (2011).10.1103/PhysRevLett.106.057206 ↗
24. Bauer, U. et al. Magneto-ionic control of interfacial magnetism. Nat. Mater. 14, 174–181 (2015).10.1038/nmat4134 ↗
25. Böscke, T., Müller, J., Bräuhaus, D., Schröder, U. & Böttger, U. Ferroelectricity in hafnium oxide thin films. Appl. Phys. Lett. 99, 102903 (2011).10.1063/1.3634052 ↗
26. Park, M. H. et al. Ferroelectricity and antiferroelectricity of doped thin HfO$$2$$ -based films. Adv. Mater. 27, 1811–1831 (2015).10.1002/adma.201404531 ↗
27. Shimizu, T. et al. The demonstration of significant ferroelectricity in epitaxial Y-doped HfO$$2$$ film. Sci. Rep. 6, 32931 (2016).10.1038/srep32931 ↗
28. Wei, Y. et al. A rhombohedral ferroelectric phase in epitaxially strained Hf$$0.5$$Zr$$0.5$$O$$0.5$$ thin films. Nat. Mater. 17, 1095–1100 (2018).10.1038/s41563-018-0196-0 ↗
29. Lyu, J., Fina, I., Solanas, R., Fontcuberta, J. & Sánchez, F. Robust ferroelectricity in epitaxial Hf$$1/2$$Zr$$1/2$$O$$1/2$$ thin films. Appl. Phys. Lett. 113, 082902 (2018).10.1063/1.5041715 ↗
30. Lyu, J., Fina, I., Solanas, R., Fontcuberta, J. & Sánchez, F. Growth window of ferroelectric epitaxial Hf$$0.5$$Zr$$0.5$$O$$0.5$$ thin films. ACS Appl. Electron. Mater. 1, 220–228 (2019).10.1021/acsaelm.8b00065 ↗
31. Wei, Y. et al. Magnetic tunnel junctions based on ferroelectric Hf$$0.5$$Zr$$0.5$$O$$0.5$$ tunnel barriers. Phys. Rev. Appl. 12, 031001 (2019).10.1103/PhysRevApplied.12.031001 ↗
32. Sulzbach, M. C. et al. Unraveling ferroelectric polarization and ionic contributions to electroresistance in epitaxial Hf0.5Zr0.5O2 tunnel junctions. Adv. Electron. Mater. 1900852 (2019).10.1002/aelm.201900852 ↗
33. Pantel, D., Goetze, S., Hesse, D. & Alexe, M. Reversible electrical switching of spin polarization in multiferroic tunnel junctions. Nat. Mater. 11, 289–293 (2012).10.1038/nmat3254 ↗
34. Yin, Y. et al. Enhanced tunnelling electroresistance effect due to a ferroelectrically induced phase transition at a magnetic complex oxide interface. Nat. Mater. 12, 397–402 (2013).10.1038/nmat3564 ↗
35. Moodera, J. S., Nassar, J. & Mathon, G. Spin-tunneling in ferromagnetic junctions. Annu. Rev. Mater. Sci. 29, 381–432 (1999).10.1146/annurev.matsci.29.1.381 ↗
36. De Teresa, J. et al. Inverse tunnel magnetoresistance in Co/SrTiO$$3$$/La$$3$$Sr$$3$$MnO$$3$$ : new ideas on spin-polarized tunneling. Phys. Rev. Lett. 82, 4288 (1999).10.1103/PhysRevLett.82.4288 ↗
37. Tsymbal, E. Y., Sokolov, A., Sabirianov, I. & Doudin, B. Resonant inversion of tunneling magnetoresistance. Phys. Rev. Lett. 90, 186602 (2003).10.1103/PhysRevLett.90.186602 ↗
38. Cauro, R. et al. Persistent and transient photoconductivity in oxygen-deficient La$$2/3$$Sr$$2/3$$MnO$$2/3$$ thin films. Phys. Rev. B 63, 174423 (2001).10.1103/PhysRevB.63.174423 ↗
39. Ge, C. et al. Metal-insulator transition induced by oxygen vacancies from electrochemical reaction in ionic liquid-gated manganite films. Adv. Mater. Interfaces 2, 1500407 (2015).10.1002/admi.201500407 ↗
40. Marún, I. V., Postma, F., Lodder, J. & Jansen, R. Tunneling magnetoresistance with positive and negative sign in La$$0.67$$Sr$$0.67$$MnO$$0.67$$/SrTiO$$0.67$$/Co junctions. Phys. Rev. B 76, 064426 (2007).10.1103/PhysRevB.76.064426 ↗
41. Schlueter, C. et al. Evidence of electronic band redistribution in La$$0.65$$Sr$$0.65$$MnO$$0.65$$ by hard x-ray photoelectron spectroscopy. Phys. Rev. B 86, 155102 (2012).10.1103/PhysRevB.86.155102 ↗
42. Yao, L., Inkinen, S. & Van Dijken, S. Direct observation of oxygen vacancy-driven structural and resistive phase transitions in La$$2/3$$Sr$$2/3$$MnO$$2/3$$. Nat. Commun. 8, 14544 (2017).10.1038/ncomms14544 ↗
43. Qin, Q. H. et al. Resistive switching in all-oxide ferroelectric tunnel junctions with ionic interfaces. Adv. Mater. 28, 6852–6859 (2016).10.1002/adma.201504519 ↗
44. Kim, D. et al. Ferroelectric tunnel memristor. Nano Lett. 12, 5697–5702 (2012).10.1021/nl302912t ↗
45. Waser, R., Dittmann, R., Staikov, G. & Szot, K. Redox-based resistive switching memories-nanoionic mechanisms, prospects, and challenges. Adv. Mater. 21, 2632–2663 (2009).10.1002/adma.200900375 ↗
46. O’donnell, J., Andrus, A., Oh, S., Colla, E. & Eckstein, J. Colossal magnetoresistance magnetic tunnel junctions grown by molecular-beam epitaxy. Appl. Phys. Lett. 76, 1914 (2000).10.1063/1.126210 ↗
47. Sawa, A. Resistive switching in transition metal oxides. Mater. Today 11, 6 (2008).10.1016/S1369-7021(08)70119-6 ↗
48. Waser, R. & Aono, M. Nanoionics-based resistive switching memories. Nat. Mater. 6, 833–840 (2007).10.1038/nmat2023 ↗
49. Seo, S. et al. Reproducible resistance switching in polycrystalline NiO films. Appl. Phys. Lett. 85, 5655 (2004).10.1063/1.1831560 ↗
50. Simmons, J. & Verderber, R. New conduction and reversible memory phenomena in thin insulating films. Proc. R. Soc. A. 301, 77–102 (1967).10.1098/rspa.1967.0191 ↗
51. Choi, B. et al. Resistive switching mechanism of TiO$$2$$ thin films grown by atomic-layer deposition. J. Appl. Phys. 98, 033715 (2005).10.1063/1.2001146 ↗
52. Gruverman, A. et al. Tunneling electroresistance effect in ferroelectric tunnel junctions at the nanoscale. Nano Lett. 9, 3539–3543 (2009).10.1021/nl901754t ↗
53. Hoffmann, M. et al. Stabilizing the ferroelectric phase in doped hafnium oxide. J. Appl. Phys. 118, 072006 (2015).10.1063/1.4927805 ↗
54. Starschich, S., Menzel, S. & Böttger, U. Evidence for oxygen vacancies movement during wake-up in ferroelectric hafnium oxide. Appl. Phys. Lett. 108, 032903 (2016).10.1063/1.4940370 ↗
55. De Teresa, J. M. et al. Role of metal-oxide interface in determining the spin polarization of magnetic tunnel junctions. Science 286, 507–509 (1999).10.1126/science.286.5439.507 ↗
56. LeClair, P. et al. Sign reversal of spin polarization in Co/Ru/Al$$2$$O$$2$$/Co magnetic tunnel junctions. Phys. Rev. B 64, 100406(R) (2001).10.1103/PhysRevB.64.100406 ↗
57. Valencia, S. et al. Interface-induced room-temperature multiferroicity in BaTiO$$3$$. Nat. Mater. 10, 753–758 (2011).10.1038/nmat3098 ↗
58. Zhang, S. Spin-dependent surface screening in ferromagnets and magnetic tunnel junctions. Phys. Rev. Lett. 83, 640 (1999).10.1103/PhysRevLett.83.640 ↗
59. Zhuravlev, M. Y., Maekawa, S. & Tsymbal, E. Y. Effect of spin-dependent screening on tunneling electroresistance and tunneling magnetoresistance in multiferroic tunnel junctions. Phys. Rev. B 81, 104419 (2010).10.1103/PhysRevB.81.104419 ↗
60. Bowen, M. et al. Bias-crafted magnetic tunnel junctions with bistable spin-dependent states. Appl. Phys. Lett. 89, 103517 (2006).10.1063/1.2345592 ↗
61. Klyukin, K., Tao, L., Tsymbal, E. Y. & Alexandrov, V. Defect-assisted tunneling electroresistance in ferroelectric tunnel junctions. Phys. Rev. Lett. 121, 056601 (2018).10.1103/PhysRevLett.121.056601 ↗