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"Tunable ultrastrong magnon–magnon coupling and spin Hall magnetoresistance in a van der Waals antiferromagnet"
C. W. F. Freeman, Z. Xue, A. K. Budniak, H. De Libero, T. Thomson, M. Bosman, G. Eda, H. Kurebayashi and M. Cubukcu
arXiv:2403.15558

"Spin-glass states generated in van der Waals magnet Cr2Ge2Te6 by alkali-ion intercalation"
S. Khan, E. S. Y. Aw, L. A. V. Nagle-Cocco, A. Sud, S. Ghosh, M. K. B. Subhan, Z. Xue, C. Freeman, D. Sagkovits, A. Guti´errez-Llorente, I. Verzhbitskiy, D. M. Arroo, C. W. Zollitsch, G. Eda, E. J. G. Santos, S. E. Dutton, S. T. Bramwell, C. A. Howard, and H. Kurebayashi
arXiv:2312.17554

"Ultrafast thermal control of spins in a 2D van der Waals magnet"
M. Dabrowski, S. Haldar, S. Khan, P. Keatley, D. Sagkovits, Z. Xue, C. Freeman, I. Verzhbitskiy, T. Griepe, U. Atxitia, G. Eda, H. Kurebayashi, E. J. G. Santos, R. Hicken

"Neuromorphic over-parameterisation: generalisation and few-shot learning in multilayer physical neural networks"
K. Stenning, J. Gartside, L. Manneschi, C. Cheung, T. Chen, A. Vanstone, J. Love, H. Holder, F. Caravelli, H. Kurebayashi, K. Everschor-Sitte, E. Vasilaki and W. Branford

Accepted/published

"Ultrastrong Magnon-Magnon Coupling and Chiral Spin-Texture Control in a Dipolar 3D Multilayered Artificial Spin-Vortex Ice"
T. Dion, K. D. Stenning, H. H. Holder, A. Vanstone, R. Sultana, G. Alatteli, M. T. Kaffash, V. Martinez, T. Kimura, H. Kurebayashi, W. R. Branford, E. Iacocca, B. M. Jungfleisch and J. C. Gartside
Nature Comm.; arXiv:2306.16159.

"Task-adaptive physical reservoir computing"
O. Lee, T. Wei, K. D. Stenning, J. C. Gartside, D. Prestwood, S. Seki, A. Aqeel, K. Karube, N. Kanazawa, Y. Taguchi, C. Back, Y. Tokura, W. R. Branford and H. Kurebayashi, 
Nature Mater. 23, 79 (2024)arXiv:2209.06962; Reserach Briefing.

"Effect of multi-layering and crystal orientation on spin-orbit torque efficiency in Ni/Pt layer stacking"
A. Sud, Y.-C. Lau, J. Brierley, H. Kurebayashi, and T. Seki
Phys. Rev. Mater. 7, 124410 (2023); arXiv:2311.13835.

"Controlling spin pumping into superconducting Nb by proximity-induced spin-triplet Cooper pairs"
A. K. Chan, M. Cubukcu, X. Montiel, S. Komori, A. Vanstone, J. E. Thompson, G. K. Perkins, M. Blamire, J. Robinson, M. Eschrig, H. Kurebayashi and L. F Cohen,
Commun. Phys. 6, 287 (2023); arXiv:2202.01520.

"Ferromagnetic resonance in two-dimensional van der Waals magnets"
C. Tang, L. Alahmed, M. Mahdi, Y. Xiong, J. Inman, N. J. McLaughlin, C. Zollitsch, T. H. Kim, C. R. Du, H. Kurebayashi, E. J. G. Santos, W. Zhang, P. Li, W. Jin   
Phys. Rep. 1032, 1 (2023); arXiv:2301.09822

"Magnon-magnon coupling in synthetic ferrimagnets"
A. Sud, K. Yamamoto, K. Z. Suzuki, S. Mizukami and H. Kurebayashi
Phys. Rev. B 108, 104407 (2023); arXiv:2307.06888

"Perspective on unconventional computing using magnetic skyrmions"
O. Lee, R. Msiska, M. A. Brems, M. Klaui, H. Kurebayashi, and K. Everschor-Sitte, 
Appl. Phys. Lett. 122, 260501 (2023)arXiv:2303.00708.

"Probing spin dynamics of ultra-thin van der Waals magnets via photon-magnon coupling"
C. W. Zollitsch, S. Khan, V. T. Trung Nam, I. A. Verzhbitskiy, D. Sagkovits, J. O’Sullivan, O. W. Kennedy, M. Strungaru, E. J. G. Santos, J. J. L. Morton, G. Eda and H. Kurebayashi,
Nature Comm. 14, 2619 (2023)arXiv:2206.02460.

"Laser-induced topological spin switching in a 2D van der Waals magnet"
M. Khela, M. Dabrowski, S. Khan, P. S. Keatley, I. Verzhbitskiy, G. Eda, R. J. Hicken, H. Kurebayashi and E. J. G. Santos,
Nature Comm. 14, 1378 (2023);  arXiv:2302.06964.

"Nonlinear magnon polaritons"
O. Lee, K. Yamamoto, M. Umeda, C. W. Zollitsch, M. Elyasi, T. Kikkawa, E. Saitoh, G. E. W. Bauer and H. Kurebayashi, 
Phys. Rev. Lett. 130, 046703 (2023)arXiv:2201.10889; Appeared On the Cover.

"Reconfigurable Training and Reservoir Computing via Spin-Wave Fingerprinting in an Artificial Spin-Vortex Ice"
J. C. Gartside, K. D. Stenning, A. Vanstone, T. Dion, H. H. Holder, D. M. Arroo, H. Kurebayashi and W. R. Branford, 
Nature Nanotech. 17, 460 (2022); arXiv:2107.08941: News and Views 

"Magnetism, symmetry and spin transport in van der Waals layered systems"
H. Kurebayashi,  J. H. Garcia, S. Khan, J. Sinova and S. Roche, 
Nature Rev. Phys. 4, 150 (2022); arXiv:2107.03763.

coverprl2023

"Memristors, Spintronics and 2D Materials for Future Computing Systems"
D. Joksas, A. AlMutairi, O. Lee, M. Cubukcu, A. Lombardo, H. Kurebayashi, A. J. Kenyon and A. Mehonic,
Adv. Intell. Syst., 4: 2200068. (2022)arXiv:2203.06147.

"Observation and control of collective spin-wave mode hybridisation in chevron arrays and square, staircase and brickwork artificial spin ices"
T. Dion, J. C. Gartside, A. Vanstone, K. D. Stenning, D. M. Arroo, H. Kurebayashi and W. R. Branford,
Phys. Rev. Research. 4, 013107 (2022)arXiv:2112.05354.

"Tunable gigahertz dynamics of low-temperature skyrmion lattice in a chiral magnet"
O. Lee, J. Sahliger, A. Aqeel, S. Khan, S. Seki, H. Kurebayashi and C. Back,
J. Phys. Condens. Matter. 34, 095801 (2022)arXiv:2111.13004.

"Tailoring interfacial effect in multilayers with Dzyaloshinskii-Moriya interaction by helium ion irradiation"
A. Sud, S. Tacchi, D. Sagkovits, C. Barton, M. Sall, L. H. Diez, E. Stylianidis, N. Smith, L. Wright, S. Zhang, X. Zhang, D. Ravelosona, G. Carlotti, H. Kurebayashi, O. Kazakova, and M. Cubukcu,
Sci. Rep. 11, 23626 (2021)arXiv:2105.03976.

"Coupling of microwave photons to topological spin-textures in Cu2OSeO3"
S. Khan, O. Lee, T. Dion, C. W. Zollitsch, S. Seki, Y. Tokura J. D. Breeze, and H. Kurebayashi, 
Phys. Rev. B 104, L100402 (2021)arXiv:2105.03719.

"Charge density waves in electron-doped molybdenum disulfide"
M. K. B. Subhan, A. Suleman, G. Moore, P. Phu, M. Hoesch, H. Kurebayashi, C. A. Howard, and S. R. Schofield,
Nano Lett. 21, 5516−5521 (2021)arXiv:2108.07015.

"Reconfigurable magnonic mode-hybridisation and spectral control in a bicomponent artificial spin ice"
J. C. Gartside, A. Vanstone, T. Dion, K. D. Stenning, D. M. Arroo, H. Kurebayashi, W. R. Branford, 
Nature Comm. 12, 2488 (2021)arXiv:2101.07767.

“Quantum engineering with hybrid magnonics systems and materials"
D. D. Awschalom, C. H. R. Du, R. He, F. J. Heremans, A. Hoffmann, J. Hou, H. Kurebayashi, Y. Li, L. Liu, V. Novosad, J. Sklenar, S. E. Sullivan, D. Sun, H. Tang, V. Tiberkevich, C. Trevillian, A. W. Tsen, L. R. Weiss, W. Zhang,  X. Zhang, L. Zhao, and C. W. Zollitsch.
IEEE Transactions on Quantum Engineering, 2 1-36 (2021)arXiv:2102.03222.

"Parity-controlled spin-wave excitations in synthetic antiferromagnets"
A. Sud, Y. Koike, S. Iihama, C. Zollitsch, S. Mizukami, and H. Kurebayashi, 
Appl. Phys. Lett. 118, 032403 (2021)arXiv:2012.12999.

"Growth, strain and spin orbit torques in epitaxial NiMnSb films sputtered on GaAs"
N. Zhao, A. Sud, H. Sukegawa, S. Komori, K. Rogdakis, K. Yamanoi, J. Patcett., J. W. A. Robinson, C. Ciccarelli and H. Kurebayashi 
Phys. Rev. Materials 5, 014413 (2021)arXiv:2012.02568.

"Spin-orbit coupling suppression and singlet-state blocking of spin-triplet Cooper pairs"
S. Komori, J. Devine-Stoneman, K. Ohnishi, G. Yang, Z. Devizorova, S. Mironov, X. Montiel, L. A. B. Olde Olthof, L. F. Cohen, H. Kurebayashi, M. G. Blamire, A. I. Buzdin, J. W. A. Robinson, 
Sci. Adv. 7 eabe0128 (2021)arXiv:2006.16654.

"Tunable magnon-magnon coupling in synthetic antiferromagnets"
A. Sud, C. W. Zollitsch, A. Kamimaki, T. Dion, S. Khan, S. Iihama, S. Mizukami, and H. Kurebayashi
Phys. Rev. B 102, 100403(R) (2020); arXiv:2006.11633v2.

"Controlling the magnetic anisotropy in Cr2Ge2Te6 by electrostatic gating"
I. A. Verzhbitskiy, H. Kurebayashi, H. Cheng, J. Zhou, S. Khan, Y. P. Feng and G. Eda,
Nature Electron. 3, 460 (2020)arXiv:2001.10217.

"Tunable pure spin supercurrents and the demonstration of their gateability in a spin-wave device"
K.-R. Jeon, X. Montiel, C. Ciccarelli, H. Kurebayashi, L. F. Cohen, S. Komori, M. G. Blamire and J. W.A. Robinson, 
Phys. Rev. X 10, 031020 (2020)arXiv:1908.00873

"Perpendicularly Magnetized Ni/Pt(001) Epitaxial Superlattice"
T. Seki, M. Tsujikawa, K. Ito, K. Uchida,  H. Kurebayashi, M. Shirai, and K. Takanashi, 
Phys. Rev. Mater. 4, 064413 (2020)arXiv:2001.11127.

"A spin dynamics study in layered van der Waals single crystal, Cr2Ge2Te6"
S. Khan, C. W. Zollitsch, D. M. Arroo, H. Cheng, I. Verzhbitskiy, A. Sud, Y. P. Feng, G. Eda and H. Kurebayashi. 
Phys. Rev. B 100, 134437 (2019)arXiv:1903.00584.

"Tunable Magnetisation Dynamics in Artificial Spin Ice via Shape Anisotropy Modification"
T. Dion, D. M. Arroo, K. Yamanoi, T. Kimura, J. C. Gartside, L. F. Cohen, H. Kurebayashi and W. R. Branford.
Phys. Rev. B 100, 054433 (2019).

"Bolometric ferromagnetic resonance techniques for characterising spin-Hall effect at high temperatures"
P. Phu, K. Yamanoi, K. Ohnishi, J. Hyodo, K. Rogdakis, Y. Yamazaki, T. Kimura, and H. Kurebayashi.
J. Magn. Magn. Mater. 485, 304-307 (2019).

"Abrikosov vortex nucleation and its detrimental effect on superconducting spin pumping in Pt/Nb/NiFe/Nb/Pt proximity structures"
K.-R. Jeon, C. Ciccarelli, H. Kurebayashi, L. F Cohen, S. Komori, J. W. A. Robinson, M. G. Blamire. 
Phys. Rev. B 99, 144503 (2019); arXiv:1902.03862.

"Magnon-photon coupling in a non-collinear magnetic insulator Cu2OSeO3"
L. V. Abdurakhimov, S. Khan, N. A. Panjwani, J. D. Breeze, M. Mochizuki, S. Seki, Y. Tokura, J. J. L. Morton and H. Kurebayashi. 
Phys. Rev. B 99, 140401R (2019). Editors' Suggestion; arXiv:1802.07113.

"Spin transport parameters of NbN thin films characterised by spin pumping experiments"
K. Rogdakis, A. Sud, M. Amado, C. M. Lee, L. McKenzie-Sell, K.-R. Jeon, M. Cubukcu, M. G. Blamire, J. W. A. Robinson, L. F. Cohen and H. Kurebayashi. 
Phys. Rev. Materials 3, 014406 (2019)arXiv:1901.05753.

"Effect of Meissner screening and trapped magnetic flux on magnetization dynamics in thick Nb/Ni80Fe20/Nb trilayers"
K.-R. Jeon, C. Ciccarelli, H. Kurebayashi, L. F. Cohen, X. Montiel, M. Eschrig, T. Wagner, S. Komori, A. Srivastava, J. W. A. Robinson, M. G. Blamire. 
Phys. Rev. Applied 11, 014061 (2019)arXiv:1810.08443.

"Exchange-field enhancement of superconducting spin pumping"
K.-R. Jeon, C. Ciccarelli, H. Kurebayashi, L. F. Cohen, X. Montiel, M. Eschrig, S. Komori, J. W. A. Robinson, M. G. Blamire. 
Phys. Rev. B 99, 024507 (2019).

"Spin-pumping-induced inverse spin-Hall effect in Nb/NiFe bilayers and its strong decay across the superconducting transition temperature"
K.-R. Jeon, C. Ciccarelli, H. Kurebayashi, J. Wunderlich, L. F. Cohen, S. Komori, J. W. A. Robinson and M. G. Blamire. 
Phys. Rev. Applied 10, 014029 (2018).

"Crystal structure and crystal growth of the polar ferrimagnet CaBaFe4O7"
R. S. Perry, H. Kurebayashi, A. Gibbs and M. Gutmann.
Phys. Rev. Materials 2, 054403 (2018).

"Enhanced spin pumping into superconductors provides evidence for superconducting pure spin currents"
K.-R. Jeon, C. Ciccarelli, A. J. Ferguson, H. Kurebayashi, L. F.  Cohen, X. Montiel, M. Eschrig, J. W. A. Robinson and M. G. Blamire. 
Nature Mater. 17 499 (2018).

"Electric power transfer in spin pumping experiments"
K. Rogdakis, N. Alfert, A. Srivastava, J. W. A. Robinson, M. G. Blamire, L. F. Cohen and H. Kurebayashi.
Appl. Phys. Express 11, 013004 (2018)arXiv:1709.04690.

"Spintronics: Anatomy of spin-orbit torques"
K. Yamamoto and H.  Kurebayashi.
Nature Nanotech. 12, 941 (2017).

"Spin-orbit torques: Go in the right direction"
H. Kurebayashi. 
Nature Phys. 13, 209 (2016).

"Complementary spin-Hall and inverse spin-galvanic effect torques in a ferromagnet/semiconductor bilayer"
T.D. Skinner, K. Olejník, L. K. Cunningham, H. Kurebayashi, R.P. Campion, B.L. Gallagher, T. Jungwirth and A.J. Ferguson. 
Nature Comm. 6, 6730 (2015).

"Magnonic charge pumping via spin-orbit coupling"
C. Ciccarelli, K. M. D. Hals, A. Irvine, V. Novak, Y. Tserkovnyak, H. Kurebayashi, A. Brataas and A. Ferguson. 
Nature Nanotech. 10, 50 (2015) News&Views.

"An anti-damping spin-orbit torque originating from the Berry curvature"
H. Kurebayashi, J. Sinova, D. Fang, A. C. Irvine, T. D. Skinner, J. Wunderlich, V. Novak, R. P. Campion, B. L. Gallagher, E. K. Vehstedt, L. P. Zarbo, K. Vyborny, A. J. Ferguson and  T. Jungwirth. 
Nature Nanotech. 9, 211 (2014) News&Views

"Electric control of the spin-Hall effect by inter-valley transitions"
N. Okamoto, H. Kurebayashi,  T. Trypiniotis, I. Farrer, D. A. Ritchie, E. Saitoh, J. Sinova, J. Masek, T. Jungwirth, and C. H. W. Barnes.
Nature Mater. 13, 932 (2014)

"Polaron Spin Current Transport in Organic Semiconductors"
S. Watanabe, K. Ando, K. Kang, S. Mooser, Y. Vaynzof, H. Kurebayashi, E. Saitoh, and H. Sirringhaus. 
Nature Phys. 10, 308 (2014) News&Views

"Spin-orbit torque opposing the Oersted torque in ultrathin Co/Pt bilayers"
T.D. Skinner, M. Wang, A.T. Hindmarch, A.W. Rushforth, A.C. Irvine, D. Heiss, H. Kurebayashi and A.J. Ferguson. 
Appl. Phys. Lett. 104, 062401 (2014).

"Uniaxial anisotropy of two-magnon scattering in an ultrathin epitaxial Fe layer on GaAs"
H. Kurebayashi, T. D. Skinner, K. Khazen, K. Olejn.ık, D. Fang, C. Ciccarelli, R. P. Campion, B. L. Gallagher, L. Fleet, A. Hirohata and A. J. Ferguson. 
Appl. Phys. Lett. 102, 082415 (2013).

"Control of Pure Spin Current by Magnon Tunneling and Three-Magnon Splitting in Insulating Yttrium Iron Garnet Films"
O. Dzyapko, H. Kurebayashi, V. E. Demidov, and S. O. Demokritov. 
Book chapter in Recent Advances in Magnetic Insulators - From Spintronics to Microwave Applications, 83 (2013).

"Effect of the magnetic film thickness on the enhancement of the spin current by multi-magnon processes"
O. Dzyapko, H. Kurebayashi, V. E. Demidov, M. Evelt, A. J. Ferguson, and S. O. Demokritov. 
Appl. Phys. Lett. 102, 252409 (2013).

"Enhanced Inverse Spin-Hall Effect in Ultrathin Ferromagnetic/Normal Metal Bilayers"
T.D. Skinner, H. Kurebayashi, D. Fang, D. Heiss, A.C. Irvine, A.T. Hindmarch, M. Wang, A.W. Rushforth and A.J.Ferguson. 
Appl. Phys. Lett. 102, 072401 (2013).

"Electrical excitation and detection of magnetic dynamics with impedance matching"
D Fang, T Skinner, H Kurebayashi, RP Campion, BL Gallagher and AJ Ferguson. 
Appl. Phys. Lett. 101, 182402 (2012).

"Characterisation of ferromagnetic rings for zernike phase plates using the Aharonov-Bohm effect"
C. J. Edgcombe, A. Ionescu, J. C. Loudon, A. M. Blackburn, H. Kurebayashi and C. H. W. Barnes. 
Ultramicroscopy 120, 78 (2012).

"Controlled enhancement of spin current emission by three-magnon splitting"
H. Kurebayashi, O. Dzyapko, V.E. Demidov, D. Fang, A. J. Ferguson and S.O. Demokritov. 
Nature Mater. 10 660 (2011) News&Views

"Spin-orbit-driven ferromagnetic resonance"
D. Fang, H. Kurebayashi, J. Wunderlich, K. Výborný, L. P. Zârbo, R. P. Campion, A. Casiraghi, B. L. Gallagher, T. Jungwirth and A. J. Ferguson. 
Nature Nanotech. 6 413 (2011).

"Electrically tunable spin injector free from the impedance mismatch problem"
K. Ando, S. Takahashi, J. Ieda, H. Kurebayashi, T. Trypiniotis, C. W. H. Barnes, S. Maekawa and E. Saitoh. 
Nature Mater. 10 655 (2011). News&Views

"Spin pumping by parametrically excited short-wavelength spin waves"
H. Kurebayashi, O. Dzyapko, V.E. Demidov, D. Fang, A. J. Ferguson and S.O. Demokritov. 
Appl. Phys. Lett. 99 162502 (2011).

"Spin current depolarization under high electric fields in undoped InGaAs"
N. Okamoto, H. Kurebayashi, K. Harii, Y. Kajiwara, H. Beere, I. Farrer, T. Trypiniotis, K. Ando, D. A. Ritchie, C. H. W. Barnes, and E. Saitoh. 
Appl. Phys. Lett. 98 242104 (2011).

 "Spin transport in germanium at room temperature"
C. Shen, T. Trypiniotis, K. Y. Lee, S. N. Holmes, R. Mansell, M. Husain, V. Shah, X. V. Li, H. Kurebayashi, I. Farrer, C. H. de Groot, D. R. Leadley, G. Bell, E. H. C. Parker, T. Whall, D. A. Ritchie, and C. H. W. Barnes. 
Appl. Phys. Lett. 97 162104 (2010)

"Electrical determination of spin relaxation time of photoexcited electrons in GaAs"
H. Kurebayashi,T. Trypiniotis, K. Lee, S. Easton, A. Ionescu, I. Farrer, D. A. Ritchie, J. A. C. Bland, and C. H. W. Barnes. 
Appl. Phys. Lett. 96,022505 (2010).

"Numerical model for spin-dependent transport of photoexcited electrons across Fe/GaAs(001) interfaces"
H. Kurebayashi, T Trypiniotis, K Lee, C Moutafis, S Easton, A Ionescu, J A C Bland and C H W Barnes. 
J. Phys. D: Appl. Phys. 43 305001 (2010).

"Spin-engineering in the Co75Fe25/Cu(110) system"
S. Easton, D. Kupper, A. Ionescu, H. Kurebayashi and C. W. H. Barnes.
J. Magn. Mater. Magn. 322 2493 (2010).

"The Initial Growth Mode of Co on Cu(311)"
S. Easton, A. Ionescu, H. Kurebayashi and C. W. H. Barnes. 
J. Appl. Phys. 107 09E101 (2010).

"Schottky Barrier Height in Fe/GaAs Films"
L. R. Fleet, K. Yoshida, H. Kobayashi, Y. Ohno, H. Kurebayashi, J.-Y. Kim, C. H. W. Barnes, and A. Hirohata. 
IEEE TRANS. MAG. 46 1737 (2010).

 "Spin polarization control through resonant states in an Fe/GaAs Schottky barrier"
S. Honda, H. Itoh, and J. Inoue, H. Kurebayashi, T. Trypiniotis, C. H. W. Barnes, A. Hirohata, and J. A. C. Bland. 
Phys. Rev. B 78 245316 (2008).

"Effect of MgO barriers on ferromagnetic metallic layers studied by polarized neutron reflectivity"
J.-B. Laloë, A. Ionescu, S. Easton, N.-J. Steinke, H. Kurebayashi, J. A. C. Bland, T. R. Charlton, and S. Langridge. 
Appl. Phys. Lett. 93, 102505 (2008)

"Distinct evolution of magnetism and anisotropy of ultrathin CoFe and Co films on Cu(110) upon gas adsorption"
D. Kupper, A. Ionescu, S. Easton, H. Kurebayashi, et al. 
J. Appl. Phys. 103 07C911 (2008).

"Initial/final state selection of the spin polarization in electron tunneling across an epitaxial Fe/GaAs(001) interface"
H. Kurebayashi. S. J. Steinmuller, J. B. Laloë, T. Trypiniotis, S. Easton, A. Ionescu, J. R. Yates, and J. A. C. Bland 
Appl. Phys. Lett. 91, 102114 (2007).

"Structural and magnetic properties of epitaxial L21-structured Co2(Cr,Fe)Al films grown on GaAs(001) substrates"
A. Hirohata, H. Kurebayashi, S. Okamura, N. Tezuka, K. Inomata. 
J. Appl. Phys. 97 103714 (2005).

"Magnetic properties of L21-structured Co2(Cr,Fe)Al films grown on GaAs(001) substrates"
A. Hirohata, H. Kurebayashi, S. Okamura, N. Tezuka, K. Inomata. 
J. Appl. Phys. 97 10C308 (2005).

"Magnetoresistance in tunnel junctions using Co2(Cr,Fe)Al full Heusler alloys"
K. Inomata, N. Tezuka, S. Okamura, H. Kurebayashi and A. Hirohata. 
J. Appl. Phys. 95 7234 (2004).