Antiferromagnetic coulpling in spintronics

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Antiferromagnetic coulpling in spintronics
Tomas Jungwirth
Institute of Physics ASCR Charles Univ., Czech
Rep.
Univ. of Nottingham, UK
Hitachi and Univ. Cambridge, UK Japan
Politecnico di Milano, Italy
Univ. of California, Berkeley
Institut de Ciencia de Materials de Barcelona,
Spain
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Giant magnetoresistance (GMR) multilayers the
dawn of spintronics
Fert, Grünberg, et al. 1988 Nobel Prize 2007
Antiferromagnetic arrangement of a ferromagnetic
multilayer at B0
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Writing information in spin-valve towards
spintronic memory (MRAM)
1. AFM coupling between FMs at B0
2. One FM flips harder than the other FM
3. One FM pinned by AFM material
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Towards reliable switching of a particular MRAM
bit
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Toggle switching ? first commercial MRAMs
FM
Synthetic AFM
FM
Fixed FM
AFM
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Read-out Giant magnetoresistance (GMR)
Ie
Ie
Fert, Grünberg, et al. 1988 Nobel Prize 2007
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Read-out Anisotropic magnetoresistance
(AMR) Spintronic effect 150 years ahead of time
M
Ie
Kelvin, 1857
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Read-out Anisotropic magnetoresistance
(AMR) Spintronic effect 150 years ahead of time
M
Ie
Kelvin, 1857
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Ohmic AMR
Kelvin, 1857
Magnetization-orientation-dependent
scattering Relativistic spin-orbit coupling
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Ohmic GMR
Fert, Grünberg, 1988
Spin-channel-dependent scattering Non-relativistic
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Tunneling magnetoresistance (TMR)
Julliere 1975, Moodera et al., Miyazaki Tezuka
1995
MRAM
Spin-channel-dependent tunneling
DOS Non-relativistic
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Tunneling anisotopic magnetoresistance (TAMR)
Gould, TJ et al. PRL 04
Magnetization-orientation-dependent tunneling
DOS Relativistic spin-orbit coupling
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Two paradigms for spintronics
Mott two-spin-channel model of ferromagnets
I
I
Mott, 1936
Dirac relativistic spin-orbit coupling
Dirac, 1928
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Antiferromagnetic MATERIALS playing ACTIVE role
in spintronics
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Spin-valve with AFM electrode
Park, Marti, Wunderlich,TJ et al. Nature Mat.
11, PRL 12
Pt
NiFe
MgO
NiFe
MnIr
Ta/Ru/Ta
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Spin-valve with AFM electrode
Park, Marti, Wunderlich,TJ et al. Nature Mat.
11, PRL 12
NiFe
Pt
MgO
NiFe
MnIr
Ta/Ru/Ta
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Spin-valve with AFM electrode
Park, Marti, Wunderlich,TJ et al. Nature Mat.
11, PRL 12
Pt
MgO
NiFe
Ta/Ru/Ta
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Spin-valve with AFM electrode
Park, Marti, Wunderlich,TJ et al. Nature Mat.
11, PRL 12
1.5 3nm IrMn
4K
gt100 spin-valve-like signal at 50 mT
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Spin-valve with AFM electrode
Park, Marti, Wunderlich,TJ et al. Nature Mat.
11, PRL 12
Electrically measurable memory effect in AFM
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Spin-valve with AFM electrode
Park, Marti, Wunderlich,TJ et al. Nature Mat.
11, PRL 12
Small signal in control sample without IrMn
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Spin-valve with AFM electrode
Writing by exchange-spring rotation of AFM by FM

Scholl et al. PRL 04
B
See also Wang et al. PRL 12 room-T AFM TAMR in
CoPt/IrMn/AlOx/Pt
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Spin-valve with AFM electrode
Shick, TJ et al. PRB 10 see also Zemen, TJ et
al. arXiv1301.5369
spin-orbit coupling
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Spin-valve with AFM electrode
Relativistic ab initio density-of-states
anisotropy
Ferromagnets
Antiferromagnets
IrMn, AuMn,...
Shick, Wunderlich, TJ et al. PRB 10
Park, Wunderlich, Joo, Jung, Shin, TJ et al.
PRL08
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AFM tunnel junction written by field-cool without
FM
Petti, Marti, Bertacco, TJ et al., submitted to
APL 13
Pt

MgO
MnIr
NiFe
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AFM tunnel junction written by field-cool without
FM
Petti, Marti, Bertacco, TJ et al., submitted to
APL 13
Pt
MgO
MnIr
NiFe
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AFM tunnel junction written by field-cool without
FM
Petti, Marti, Bertacco, TJ et al., submitted to
APL 13
Pt
MgO
MnIr
Field thermal-assisted MRAM
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AFM tunnel junction written by field-cool without
FM
Petti, Marti, Bertacco, TJ et al., submitted to
APL 13
Pt
MgO
MnIr
Magnetic memory insensitive to magnetic fields
producing no stray fields
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Writing by current non-relativistic
spin-transfer torque
Spins injected from external polarizer in a
non-uniform magnetic structure
Mp
M
Berger PRB 96, Slonczewski JMMM 96
STT-MRAM
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Writing by current non-relativistic
spin-transfer torque
Spins injected from external polarizer in a
non-uniform magnetic structure
Berger PRB 96, Slonczewski JMMM 96
I
I
I
I
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Writing by current relativistic spin-orbit torque
Spin current in a uniform magnetic structure
without external polarizer
M
Manchon Zhang, PRB 08, Chernyshev et al.
Nature Phys.09, Miron et al. Nature Mater. 10,
Fang, Ferguson, TJ et al. Nature Nanotech.11
In-plane current switching
Miron et al., Nature 11
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Writing by current relativistic spin-orbit torque
Spin current in a uniform magnetic structure
without external polarizer
Andrew Ferguson, W18.00007
Manchon Zhang, PRB 08, Chernyshev et al.
Nature Phys.09, Miron et al. Nature Mater. 10,
Fang, Ferguson, TJ et al. Nature Nanotech.11
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Writing by electric field or light Magnetic
semiconductor spintronics
Petr Nemec, R18.00001
FM semiconductors
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Semiconductors more AFMs than FMs and high-TN
AFMs
TJ, Novák, Martí et al. PRB 11, Cava Viewpoint,
Physics 11, Máca, Mašek, TJ et al. JMMM 12
II-VI FM TC (K) AFM TN (K)
MnO 122
MnS 152
MnSe 173
MnTe 323
EuO 67
EuS 16
EuSe 5
EuTe 10
III-V FM TC (K) AFM TN (K)
FeN 100
FeP 115
FeAs 77
FeSb 100-220
GdN 72
GdP 15
GdAs 19
GdSb 27
II-V-IV-V FM TC (K) AFM TN (K)
MnSiN2 490
I-VI-III-VI FM TC (K) AFM TN (K)
CuFeO2 11
CuFeS2 825
CuFeSe2 70
CuFeTe2 254
I-II-V FM TC (K) AFM TN (K)
IaLi, Na,.. IbCu IIMn VSb,As, P gt room T
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Spin-orbit-coupled Mott AFM semiconductor
Kim et al., Science 09, Jin et al. PRB 09,
Arita et al. PRL 12
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Ohmic AMR in Sr2IrO4 AFM semiconductor
Xavier Martí, T18.00011
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Metal AFM spintronics
B.G. Park, J. Wunderlich, X. Marti, V. Holy, Y.
Kurosaki, M. Yamada, H. Yamamoto, A. Nishide, J.
Hayakawa, H. Takahashi, A.B. Shick, T. Jungwirth
? Nature Mater. 10 (2011) 347 351 X. Marti, B.
G. Park, J. Wunderlich, H. Reichlova, Y.
Kurosaki, M. Yamada, H. Yamamoto, A. Nishide, J.
Hayakawa, H. Takahashi, T. Jungwirth ?? Phys.
Rev. Lett. 108 (2012) 017201(1) - 017201(4) D.
Petti, E. Albisetti, H. Reichlová, J. Gazquez, M.
Varela, M. Molina-Ruiz, A. F. Lopeandía, K.
Olejník, V. Novák, I. Fina, B. Dkhil, J.
Hayakawa, X. Marti, J. Wunderlich, T. Jungwirth,
R. Bertacco ? submitted to Appl. Phys. Lett.
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Semiconductor AFM spintronics
T. Jungwirth, V. Novák, X. Marti, M. Cukr, F.
Máca, A.B. Shick, J. Mašek, P. Horodyska, P.
Nemec, V. Holý, J. Zemek, P. Kužel, I. Nemec, B.
L. Gallagher, R. P. Campion, C. T. Foxon, J.
Wunderlich ?? Phys. Rev. B 83 (2011) 035321(1) -
035321(6). C. Rayan Serrao, Jian Liu, J.T.
Heron, G. Singh-Bhalla, A. Yadav, S.J. Suresha,
R. J. Paull, D. Yi, J.-H. Chu, M. Trassin, A.
Vishwanath, E. Arenholz, C. Frontera, J. Železný,
J. Mašek, T. Jungwirth, X. Marti, R. Ramesh
? Phys. Rev. B 87 (2013) 085121(1)-08512(6) P.
Wadley, V. Novak, R. P. Campion, C. Rinaldi, X.
Mart, H. Reichlova, J. Zelezny, J. Gazquez, M. A.
Roldan, M. Varela, D. Khalyavin, S. Langridge, D.
Kriegner,10 F. Maca, J. Masek, V. Holy, A. W.
Rushforth, K. W. Edmonds, B. L. Gallagher, C. T.
Foxon, J. Wunderlich, and T. Jungwirth, to be
published X. Marti, I. Fina, D. Yi, J. Liu, J.H.
Chu, C. Rayan-Serrao, S. Suresha, J. Železný, T.
Jungwirth, J. Fontcuberta, R. Ramesh, to be
published
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