Magnetic Tunnel Junctions and Their Applications in Non-volatile Circuits

Reference work entry

Abstract

Magnetic tunnel junctions (MTJs) have become the basic building blocks of spintronic nonvolatile circuits due to their large tunneling magnetoresistance (TMR) values for readout and the possibility to electrically write information into the devices. This chapter focuses on evaluating the performance, challenges, and design parameters of MTJ devices for nonvolatile circuits. The reading, writing, and storing functions are evaluated under the light of the different requirements of nonvolatile circuit applications and utilizing new developments in the design and realization of state-of-the-art MTJs. Finally, examples of the role of MTJs in CMOS-based and beyond-CMOS computing are presented.

Keywords

Spin Wave Free Layer Magnetic Tunnel Junction Perpendicular Anisotropy Majority Gate 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

List of Abbreviations

AP

Antiparallel state of the MTJ

BEOL

Back end of the line

CMOS

Complementary metal-oxide-semiconductor

ME

Magnetoelectric

MRAM

Magnetic random access memory

MTJ

Magnetic tunnel junction

NVM

Nonvolatile memory

P

Parallel state of the MTJ

SHE

Spin Hall effect

SOT

Spin-orbit torque

STT

Spin-transfer torque

TMR

Tunneling magnetoresistance

VCMA

Voltage-controlled magnetic anisotropy

References

  1. 1.
    Borkar S (2006) Electronics beyond nano-scale CMOS. In: Proceedings of the 43rd ACM/IEEE design automation conference, San Francisco, CA, 2006, pp 807–808Google Scholar
  2. 2.
    Moore GE (1965) Cramming more components onto integrated circuits. Electron Mag 38:114–117Google Scholar
  3. Mayberry M (2010) Emerging technologies and Moore’s law: prospects for the future. Available: http://www.nist.gov/pml/div683/upload/Mayberry_March_2010.pdf
  4. 4.
    Kuhn KJ (2012) Considerations for ultimate CMOS scaling. IEEE Trans Electron Devices 59:1813–1828CrossRefADSGoogle Scholar
  5. 5.
    Nowak EJ, Ludwig T, Aller I, Kedzierski J, Leong M, Rainey B et al (2003) Scaling beyond the 65 nm node with FinFET-DGCMOS. In: Proceedings of the IEEE custom integrated circuits conference, San Jose, 2003, pp 339–342Google Scholar
  6. 6.
    International Technology Roadmap for Semiconductors (ITRS) (2011–2012)Google Scholar
  7. 7.
    Gibbons RAA, Shi K, Keating M, Flynn D (2007) Low power methodology manual. Springer, New YorkGoogle Scholar
  8. 8.
    Rabaey J (2009) Low power design essentials. Springer, New YorkCrossRefGoogle Scholar
  9. 9.
    Burnett D, Parihar S, Ramamurthy H, Balasubramanian S (2014) FinFET SRAM design challenges. In: IEEE international conference on IC design & technology (ICICDT), Austin, pp 1–4, 2014Google Scholar
  10. 10.
    Taejoong S, Woojin R, Jonghoon J, Giyong Y, Jaeho P, Sunghyun P et al (2014) 13.2 A 14 nm FinFET 128Mb 6T SRAM with Vmin-enhancement techniques for low-power applications. In: IEEE international solid-state circuits conference digest of technical papers (ISSCC), San Francisco, 2014, pp 232–233Google Scholar
  11. 11.
    Mutlu O (2013) Memory scaling: a systems architecture perspective. In: 5th IEEE international memory workshop (IMW), Monterey, 2013, pp 21–25Google Scholar
  12. 12.
    Hamzaoglu F, Arslan U, Bisnik N, Ghosh S, Lal MB, Lindert N et al (2014) 13.1 A 1 Gb 2 GHz embedded DRAM in 22 nm tri-gate CMOS technology. In: IEEE international solid-state circuits conference digest of technical papers (ISSCC), San Francisco, 2014, pp 230–231Google Scholar
  13. 13.
    Bernstein K, Cavin RK, Porod W, Seabaugh A, Welser J (2010) Device and architecture outlook for beyond CMOS switches. Proc IEEE 98:2169–2184CrossRefGoogle Scholar
  14. 14.
    Nikonov DE, Young IA (2013) Overview of beyond-CMOS devices and a uniform methodology for their benchmarking. Proc IEEE 101:2498–2533CrossRefGoogle Scholar
  15. 15.
    Tsymbal EY, Zutic I (2011) Handbook of spin transport and magnetism. CRC press, Boca RatonGoogle Scholar
  16. 16.
    Tserkovnyak Y, Brataas A, Bauer GEW (2002) Enhanced Gilbert damping in thin ferromagnetic films. Phys Rev Lett 88:117601CrossRefADSGoogle Scholar
  17. 17.
    Saitoh E, Ueda M, Miyajima H, Tatara G (2006) Conversion of spin current into charge current at room temperature: inverse spin-Hall effect. Appl Phys Lett 88:182509CrossRefADSGoogle Scholar
  18. 18.
    Shinjo T (2013) Nanomagnetism and spintronics. Oxford, UKGoogle Scholar
  19. 19.
    Freitas PP, Ferreira R, Cardoso S, Cardoso F (2007) Magnetoresistive sensors. J Phys Condens Matter 19:165221CrossRefADSGoogle Scholar
  20. 20.
    Parkin SSP, Kaiser C, Panchula A, Rice PM, Hughes B, Samant M et al (2004) Giant tunnelling magnetoresistance at room temperature with MgO (100) tunnel barriers. Nat Mater 3:862–867CrossRefADSGoogle Scholar
  21. 21.
    Yuasa S, Nagahama T, Fukushima A, Suzuki Y, Ando K (2004) Giant room-temperature magnetoresistance in single-crystal Fe/MgO/Fe magnetic tunnel junctions. Nat Mater 3:868–871CrossRefADSGoogle Scholar
  22. 22.
    Julliere M (1975) Tunneling between ferromagnetic films. Phys Lett A 54:225–226CrossRefADSGoogle Scholar
  23. 23.
    Moodera JS, Kinder LR, Wong TM, Meservey R (1995) Large magnetoresistance at room temperature in ferromagnetic thin film tunnel junctions. Phys Rev Lett 74:3273–3276CrossRefADSGoogle Scholar
  24. 24.
    Miyazaki T, Tezuka N (1995) Giant magnetic tunneling effect in Fe/Al2O3/Fe junction. J Magn Magn Mater 139:L231–L234CrossRefADSGoogle Scholar
  25. 25.
    Lin CJ, Kang SH, Wang YJ, Lee K, Zhu X, Chen WC et al (2009) 45 nm low power CMOS logic compatible embedded STT MRAM utilizing a reverse-connection 1T/1MTJ cell. In: 2009 I.E. international electron devices meeting (IEDM), Baltimore, 2009, pp 1–4Google Scholar
  26. 26.
    Stöhr J, Siegmann HC (2007) Magnetism: from fundamentals to nanoscale dynamics. Springer, Berlin HeidelbergGoogle Scholar
  27. 27.
    Chappert C, Fert A, Van Dau FN (2007) The emergence of spin electronics in data storage. Nat Mater 6:813–823CrossRefADSGoogle Scholar
  28. 28.
    Yuasa S, Djayaprawira DD (2007) Giant tunnel magnetoresistance in magnetic tunnel junctions with a crystalline MgO(0 0 1) barrier. J Phys D Appl Phys 40:R337CrossRefADSGoogle Scholar
  29. 29.
    Butler WH, Zhang XG, Schulthess TC, MacLaren JM (2001) Spin-dependent tunneling conductance of Fe|MgO|Fe sandwiches. Phys Rev B 63:054416CrossRefADSGoogle Scholar
  30. 30.
    Mathon J, Umerski A (2001) Theory of tunneling magnetoresistance of an epitaxial Fe/MgO/Fe(001) junction. Phys Rev B 63:220403CrossRefADSGoogle Scholar
  31. 31.
    Ikeda S, Hayakawa J, Ashizawa Y, Lee YM, Miura K, Hasegawa H et al (2008) Tunnel magnetoresistance of 604 % at 300 K by suppression of Ta diffusion in CoFeB/MgO/CoFeB pseudo-spin-valves annealed at high temperature. Appl Phys Lett 93:082508CrossRefADSGoogle Scholar
  32. 32.
    Ikeda S, Sato H, Yamanouchi M, Gan H, Miura K, Mizunuma K et al (2012) Recent progress of perpendicular anisotropy magnetic tunnel junctions for nonvolatile VLSI. SPIN 02:1240003CrossRefGoogle Scholar
  33. 33.
    Yusuke S, Ryosho N, Wenhong W, Hiroaki S, Shuu’ichirou Y, Masaaki T et al (2010) A new spin-functional metal–oxide–semiconductor field-effect transistor based on magnetic tunnel junction technology: pseudo-spin-MOSFET. Appl Phys Express 3:013003CrossRefGoogle Scholar
  34. 34.
    Sugahara S, Nitta J (2010) Spin-transistor electronics: an overview and outlook. Proc IEEE 98:2124–2154CrossRefGoogle Scholar
  35. 35.
    Tang DD, Lee Y-J (2010) Magnetic memory: fundamentals and technology. Cambridge University Press, New YorkCrossRefGoogle Scholar
  36. 36.
    Alzate JG, Khalili Amiri P, Yu G, Upadhyaya P, Katine JA, Langer J et al (2014) Temperature dependence of the voltage-controlled perpendicular anisotropy in nanoscale MgO|CoFeB|Ta magnetic tunnel junctions. Appl Phys Lett 104:112410CrossRefADSGoogle Scholar
  37. 37.
    Chen E, Apalkov D, Diao Z, Driskill-Smith A, Druist D, Lottis D et al (2010) Advances and future prospects of spin-transfer torque random access memory. IEEE Trans Magn 46:1873–1878CrossRefADSGoogle Scholar
  38. 38.
    Driskill-Smith A, Apalkov D, Nikitin V, Tang X, Watts S, Lottis D et al (2011) Latest advances and roadmap for in-plane and perpendicular STT-RAM. In: 3rd IEEE international memory workshop (IMW), Monterey, CA, 2011, pp 1–3Google Scholar
  39. 39.
    Apalkov D, Watts S, Driskill-Smith A, Chen E, Diao Z, Nikitin V (2010) Comparison of scaling of in-plane and perpendicular spin transfer switching technologies by micromagnetic simulation. IEEE Trans Magn 46:2240–2243CrossRefADSGoogle Scholar
  40. 40.
    Sbiaa R, Meng H, Piramanayagam SN (2011) Materials with perpendicular magnetic anisotropy for magnetic random access memory. Phys Status Solidi (RRL) Rapid Res Lett 5:413–419CrossRefADSGoogle Scholar
  41. 41.
    Wang B, Oomiya H, Arakawa A, Hasegawa T, Ishio S (2014) Perpendicular magnetic anisotropy and magnetization of L10 FePt/FeCo bilayer films. J Appl Phys 115:133908CrossRefADSGoogle Scholar
  42. 42.
    Ikeda S, Miura K, Yamamoto H, Mizunuma K, Gan HD, Endo M et al (2010) A perpendicular-anisotropy CoFeB–MgO magnetic tunnel junction. Nat Mater 9:721–724CrossRefADSGoogle Scholar
  43. 43.
    Beleggia M, Graef MD, Millev YT, Goode DA, Rowlands G (2005) Demagnetization factors for elliptic cylinders. J Phys D Appl Phys 38:3333CrossRefADSGoogle Scholar
  44. 44.
    Sato H, Yamanouchi M, Ikeda S, Fukami S, Matsukura F, Ohno H (2012) Perpendicular-anisotropy CoFeB-MgO magnetic tunnel junctions with a MgO/CoFeB/Ta/CoFeB/MgO recording structure. Appl Phys Lett 101:022414CrossRefADSGoogle Scholar
  45. 45.
    Huai Y (2008) Spin-transfer torque MRAM (STT-MRAM): challenges and prospects. AAPPS Bull 18:33–40Google Scholar
  46. 46.
    Slonczewski JC (1996) Current-driven excitation of magnetic multilayers. J Magn Magn Mater 159:L1–L7CrossRefADSGoogle Scholar
  47. 47.
    Berger L (1996) Emission of spin waves by a magnetic multilayer traversed by a current. Phys Rev B 54:9353–9358CrossRefADSGoogle Scholar
  48. 48.
    Ralph DC, Stiles MD (2008) Spin transfer torques. J Magn Magn Mater 320:1190–1216CrossRefADSGoogle Scholar
  49. 49.
    Katine JA, Fullerton EE (2008) Device implications of spin-transfer torques. J Magn Magn Mater 320:1217–1226CrossRefADSGoogle Scholar
  50. 50.
    Liu L, Pai C-F, Li Y, Tseng HW, Ralph DC, Buhrman RA (2012) Spin-torque switching with the giant spin Hall effect of tantalum. Science 336:555–558CrossRefADSGoogle Scholar
  51. 51.
    Fan Y, Upadhyaya P, Kou X, Lang M, Takei S, Wang Z et al (2014) Magnetization switching through giant spin–orbit torque in a magnetically doped topological insulator heterostructure. Nat Mater 13:699–704CrossRefADSGoogle Scholar
  52. 52.
    Duan C-G, Jaswal SS, Tsymbal EY (2006) Predicted magnetoelectric effect in Fe/BaTiO3 multilayers: ferroelectric control of magnetism. Phys Rev Lett 97:047201CrossRefADSGoogle Scholar
  53. 53.
    Weisheit M, Fähler S, Marty A, Souche Y, Poinsignon C, Givord D (2007) Electric field-induced modification of magnetism in thin-film ferromagnets. Science 315:349–351CrossRefADSGoogle Scholar
  54. 54.
    Maruyama T, Shiota Y, Nozaki T, Ohta K, Toda N, Mizuguchi M et al (2009) Large voltage-induced magnetic anisotropy change in a few atomic layers of iron. Nat Nanotechnol 4:158–161CrossRefADSGoogle Scholar
  55. 55.
    Barnes SE, Ieda J, Maekawa S (2014) Rashba spin-orbit anisotropy and the electric field control of magnetism. Sci Rep 4:4105CrossRefADSGoogle Scholar
  56. 56.
    Sun JZ (2000) Spin-current interaction with a monodomain magnetic body: a model study. Phys Rev B 62:570–578CrossRefADSGoogle Scholar
  57. 57.
    Liu LQ, Moriyama T, Ralph DC, Buhrman RA (2009) Reduction of the spin-torque critical current by partially canceling the free layer demagnetization field. Appl Phys Lett 94:122508CrossRefADSGoogle Scholar
  58. 58.
    Amiri PK, Zeng ZM, Langer J, Zhao H, Rowlands G, Chen YJ et al (2011) Switching current reduction using perpendicular anisotropy in CoFeB-MgO magnetic tunnel junctions. Appl Phys Lett 98:112507CrossRefADSGoogle Scholar
  59. 59.
    Rahman MT, Lyle A, Amiri PK, Harms J, Glass B, Zhao H et al (2012) Reduction of switching current density in perpendicular magnetic tunnel junctions by tuning the anisotropy of the CoFeB free layer. J Appl Phys 111:07C907Google Scholar
  60. 60.
    Worledge DC, Hu G, Abraham DW, Sun JZ, Trouilloud PL, Nowak J et al (2011) Spin torque switching of perpendicular Ta vertical bar CoFeB vertical bar MgO-based magnetic tunnel junctions. Appl Phys Lett 98:022501CrossRefADSGoogle Scholar
  61. 61.
    Kim J, Zhao H, Jiang Y, Klemm A, Wang J-P, Kim CH (2014) Scaling analysis of in-plane and perpendicular anisotropy magnetic tunnel junctions using a physics-based model. In: Device research conference (DRC), 2014, Santa BarbaraGoogle Scholar
  62. 62.
    NIMO (2012) Predictive technology model. Available: http://ptm.asu.edu/
  63. 63.
    Yu C, Wei Z (2006) Predictive technology model for nano-CMOS design exploration. In: 1st international conference on nano-networks and workshops (NanoNet ’06), Lausanne, 2006, pp 1–5MATHGoogle Scholar
  64. 64.
    Sato H, Enobio ECI, Yamanouchi M, Ikeda S, Fukami S, Kanai S et al (2014) Properties of magnetic tunnel junctions with a MgO/CoFeB/Ta/CoFeB/MgO recording structure down to junction diameter of 11 nm. Appl Phys Lett 105:062403CrossRefADSGoogle Scholar
  65. 65.
    Kent AD, Ozyilmaz B, del Barco E (2004) Spin-transfer-induced precessional magnetization reversal. Appl Phys Lett 84:3897–3899CrossRefADSGoogle Scholar
  66. 66.
    Rowlands GE, Rahman T, Katine JA, Langer J, Lyle A, Zhao H et al (2011) Deep subnanosecond spin torque switching in magnetic tunnel junctions with combined in-plane and perpendicular polarizers. Appl Phys Lett 98:102509CrossRefADSGoogle Scholar
  67. 67.
    Liu H, Bedau D, Backes D, Katine JA, Langer J, Kent AD (2010) Ultrafast switching in magnetic tunnel junction based orthogonal spin transfer devices. Appl Phys Lett 97:242510CrossRefADSGoogle Scholar
  68. 68.
    Kato YK, Myers RC, Gossard AC, Awschalom DD (2004) Observation of the spin Hall effect in semiconductors. Science 306:1910–1913CrossRefADSGoogle Scholar
  69. 69.
    Pai C-F, Liu L, Li Y, Tseng HW, Ralph DC, Buhrman RA (2012) Spin transfer torque devices utilizing the giant spin Hall effect of tungsten. Appl Phys Lett 101:122404 (4 pages)CrossRefADSGoogle Scholar
  70. 70.
    Liu L, Lee OJ, Gudmundsen TJ, Ralph DC, Buhrman RA (2012) Current-induced switching of perpendicularly magnetized magnetic layers using spin torque from the spin Hall effect. Phys Rev Lett 109:096602CrossRefADSGoogle Scholar
  71. 71.
    Yu G, Upadhyaya P, Wong KL, Jiang W, Alzate JG, Tang J et al (2014) Magnetization switching through spin-Hall-effect-induced chiral domain wall propagation. Phys Rev B 89:104421CrossRefADSGoogle Scholar
  72. 72.
    Yu G, Upadhyaya P, Fan Y, Alzate JG, Jiang W, Wong KL et al (2014) Switching of perpendicular magnetization by spin-orbit torques in the absence of external magnetic fields. Nat Nanotechnol 9:548–554CrossRefADSGoogle Scholar
  73. 73.
    Brataas A, Hals KMD (2014) Spin-orbit torques in action. Nat Nanotechnol 9:86–88CrossRefADSGoogle Scholar
  74. 74.
    Mellnik AR, Lee JS, Richardella A, Grab JL, Mintun PJ, Fischer MH et al (2014) Spin-transfer torque generated by a topological insulator. Nature 511:449–451, 07/24/printCrossRefADSGoogle Scholar
  75. 75.
    Wang KL, Alzate JG, Amiri PK (2013) Low-power non-volatile spintronic memory: STT-RAM and beyond. J Phys D Appl Phys 46:074003CrossRefADSGoogle Scholar
  76. 76.
    Nikonov D (2013) Beyond CMOS computing: magnetoelectric switching. Available: http://nanohub.org/resources/18358/download/NikonovBeyondCMOS_10_magnetoelectric.pdf
  77. 77.
    Nikonov DE, Young IA (2014) Benchmarking spintronic logic devices based on magnetoelectric oxides. J Mater Res 29:2109–2115CrossRefADSGoogle Scholar
  78. 78.
    Alzate JG, Amiri PK, Cherepov S, Zhu J, Upadhyaya P, Lewis M et al (2011) Voltage-induced switching of CoFeB-MgO magnetic tunnel junctions. In: 56th conference on magnetism and magnetic materials (MMM), Scottsdale, 2011, pp EG-11Google Scholar
  79. 79.
    Alzate JG, Amiri PK, Upadhyaya P, Cherepov SS, Zhu J, Lewis M et al (2012) Voltage-induced switching of nanoscale magnetic tunnel junctions. In: IEEE international electron devices meeting (IEDM), San Francisco, 2012, pp 29.5.1–29.5.4Google Scholar
  80. 80.
    Wang W-G, Li M, Hageman S, Chien CL (2012) Electric-field-assisted switching in magnetic tunnel junctions. Nat Mater 11:64–68CrossRefADSGoogle Scholar
  81. 81.
    Shiota Y, Nozaki T, Bonell F, Murakami S, Shinjo T, Suzuki Y (2012) Induction of coherent magnetization switching in a few atomic layers of FeCo using voltage pulses. Nat Mater 11:39–43CrossRefADSGoogle Scholar
  82. 82.
    Tao W, Bur A, Zhao P, Mohanchandra KP, Wong K, Wang KL et al (2011) Giant electric-field-induced reversible and permanent magnetization reorientation on magnetoelectric Ni/(011) [Pb(Mg1/3Nb2/3)O3](1 − x)–[PbTiO3]x heterostructure. Appl Phys Lett 98:012504CrossRefADSGoogle Scholar
  83. 83.
    Zhu J, Katine JA, Rowlands GE, Chen Y-J, Duan Z, Alzate JG et al (2012) Voltage-induced ferromagnetic resonance in magnetic tunnel junctions. Phys Rev Lett 108:197203CrossRefADSGoogle Scholar
  84. 84.
    Smullen CW, Mohan V, Nigam A, Gurumurthi S, Stan MR (2011) Relaxing non-volatility for fast and energy-efficient STT-RAM caches. In: 2011 I.E. 17th international symposium on high performance computer architecture (HPCA), 2011, San Antonio, pp 50–61Google Scholar
  85. 85.
    Weisheng Z, Chappert C, Javerliac V, Noziere JP (2009) High speed, high stability and low power sensing amplifier for MTJ/CMOS hybrid logic circuits. IEEE Trans Magn 45:3784–3787CrossRefADSGoogle Scholar
  86. 86.
    Fengbo R, Markovic D (2010) True energy-performance analysis of the MTJ-based logic-in-memory architecture (1-bit full adder). IEEE Trans Electron Devices 57:1023–1028CrossRefADSGoogle Scholar
  87. 87.
    Hanyu T (2013) Challenge of MTJ/MOS-hybrid logic-in-memory architecture for nonvolatile VLSI processor. In: IEEE international symposium on circuits and systems (ISCAS), Beijing, 2013, pp 117–120Google Scholar
  88. 88.
    Suzuki D, Endoh T, Hanyu T (2008) TMR-logic-based LUT for quickly wake-up FPGA. In: 51st Midwest Symposium on Circuits and Systems, Knoxville, TN, PP 326–329Google Scholar
  89. 89.
    Matsunaga S, Katsumata A, Natsui M, Endoh T, Ohno H, Hanyu T (2012) Design of a 270ps-access 7-transistor/2-magnetic-tunnel-junction cell circuit for a high-speed-search nonvolatile ternary content-addressable memory. J Appl Phys 111:07E336CrossRefGoogle Scholar
  90. 90.
    Wang KL, Amiri PK (2012) Nonvolatile spintronics: perspectives on instant-on nonvolatile nanoelectronic systems. SPIN 02:1250009CrossRefGoogle Scholar
  91. 91.
    Khitun A, Wang KL (2005) Nano scale computational architectures with Spin Wave Bus. Superlattices Microstruct 38:184–200CrossRefADSGoogle Scholar
  92. 92.
    Wolf SA, Awschalom DD, Buhrman RA, Daughton JM, von Molnár S, Roukes ML et al (2001) Spintronics: a spin-based electronics vision for the future. Science 294:1488–1495CrossRefADSGoogle Scholar
  93. 93.
    Khitun A, Bao M, Wang KL (2008) Spin wave magnetic nanofabric: a new approach to spin-based logic circuitry. IEEE Trans Magn 44:2141–2152CrossRefADSGoogle Scholar
  94. 94.
    Alzate JG, Upadhyaya P, Lewis M, Nath J, Lin YT, Wong K et al (2012) Spin wave nanofabric update. In: 2012 IEEE/ACM international symposium on nanoscale architectures (NANOARCH), Amsterdam, pp 196–202Google Scholar
  95. 95.
    Datta S, Das B (1990) Electronic analog of the electro-optic modulator. Appl Phys Lett 56:665–667CrossRefADSGoogle Scholar
  96. 96.
    Liu C-X, Qi X-L, Dai X, Fang Z, Zhang S-C (2008) Quantum anomalous hall effect in Hg 1-y Mn y Te quantum wells. Phys Rev Lett 101:146802CrossRefADSGoogle Scholar
  97. 97.
    Qi X-L, Zhang S-C (2011) Topological insulators and superconductors. Rev Mod Phys 83:1057–1110CrossRefADSGoogle Scholar
  98. 98.
    Moore JE (2010) The birth of topological insulators. Nature 464:194–198CrossRefADSGoogle Scholar
  99. 99.
    Cherepov S, Khalili Amiri P, Alzate JG, Wong K, Lewis M, Upadhyaya P et al (2014) Electric-field-induced spin wave generation using multiferroic magnetoelectric cells. Appl Phys Lett 104:082403CrossRefADSGoogle Scholar
  100. 100.
    Csaba G, Imre A, Bernstein GH, Porod W, Metlushko V (2002) Nanocomputing by field-coupled nanomagnets. IEEE Trans Nanotechnol 1:209–213CrossRefADSGoogle Scholar

Copyright information

© Springer Science+Business Media Dordrecht 2016

Authors and Affiliations

  1. 1.Department of Electrical EngineeringUniversity of CaliforniaLos AngelesUSA

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