We use time-resolved resonant magnetic scattering experiments to investigate the laser induced demagnetization of Co/Pt multilayers with large perpendicular magnetic anisotropy. Our pump-probe approach, which relies on extreme ultraviolet pulses obtained via high-harmonic generation, allows us to monitor the temporal evolution of the system in an element-selective fashion, thus to disentangle the contributions from permanent and proximity-induced magnetic moments. By analyzing the data gathered at the Co and Pt O3 edges, we are able to show that after femtosecond laser irradiation, both components display a very similar loss of magnetic order, with almost identical demagnetization amplitudes and characteristic times, but a small delay (10–20 fs) of the Pt magnetization quenching with respect to Co. Comparing our experiments with literature results, therefore, suggests that in these 3d–5d multilayers and alloys, the different constituents remain strongly coupled after optical excitation; no matter whether the thin films possess a preferred in-plane or out-of-plane easy magnetization direction.
References
1.
P. F.
Carcia
, A. D.
Meinhaldt
, and A.
Suna
, “Perpendicular magnetic anisotropy in Pd/Co thin film layered structures
,” Appl. Phys. Lett.
47
, 178
–180
(1985
).2.
P. F.
Carcia
, “Perpendicular magnetic anisotropy in Pd/Co and Pt/Co thin-film layered structures
,” J. Appl. Phys.
63
, 5066
–5073
(1988
).3.
B. N.
Engel
, C. D.
England
, R. A.
Van Leeuwen
, M. H.
Wiedmann
, and C. M.
Falco
, “Interface magnetic anisotropy in epitaxial superlattices
,” Phys. Rev. Lett.
67
, 1910
–1913
(1991
).4.
M. T.
Johnson
, P. J. H.
Bloemen
, F. J. A.
den Broeder
, and J. J.
de Vries
, “Magnetic anisotropy in metallic multilayers
,” Rep. Prog. Phys.
59
, 1409
–1458
(1996
).5.
G.
Malinowski
, F.
Dalla Longa
, J. H. H.
Rietjens
, P. V.
Paluskar
, R.
Huijink
, H. J. M.
Swagten
, and B.
Koopmans
, “Control of speed and efficiency of ultrafast demagnetization by direct transfer of spin angular momentum
,” Nat. Phys.
4
, 855
–858
(2008
).6.
N.
Moisan
, G.
Malinowski
, J.
Mauchain
, M.
Hehn
, B.
Vodungbo
, J.
Lüning
, S.
Mangin
, E. E.
Fullerton
, and A.
Thiaville
, “Investigating the role of superdiffusive currents in laser induced demagnetization of ferromagnets with nanoscale magnetic domains
,” Sci. Rep.
4
, 4658
(2015
).7.
B.
Vodungbo
, B.
Tudu
, J.
Perron
, R.
Delaunay
, L.
Müller
, M. H.
Berntsen
, G.
Grübel
, G.
Malinowski
, C.
Weier
, J.
Gautier
, G.
Lambert
, P.
Zeitoun
, C.
Gutt
, E.
Jal
, A. H.
Reid
, P. W.
Granitzka
, N.
Jaouen
, G. L.
Dakovski
, S.
Moeller
, M. P.
Minitti
, A.
Mitra
, S.
Carron
, B.
Pfau
, C.
von Korff Schmising
, M.
Schneider
, S.
Eisebitt
, and J.
Lüning
, “Indirect excitation of ultrafast demagnetization
,” Sci. Rep.
6
, 18970
(2016
).8.
T. J.
Huisman
, R. V.
Mikhaylovskiy
, J. D.
Costa
, F.
Freimuth
, E.
Paz
, J.
Ventura
, P. P.
Freitas
, S.
Blügel
, Y.
Mokrousov
, T.
Rasing
, and A. V.
Kimel
, “Femtosecond control of electric currents in metallic ferromagnetic heterostructures
,” Nat. Nanotechnol.
11
, 455
–458
(2016
).9.
B.
Vodungbo
, J.
Gautier
, G.
Lambert
, A. B.
Sardinha
, M.
Lozano
, S.
Sebban
, M.
Ducousso
, W.
Boutu
, K.
Li
, B.
Tudu
, M.
Tortarolo
, R.
Hawaldar
, R.
Delaunay
, V.
López-Flores
, J.
Arabski
, C.
Boeglin
, H.
Merdji
, P.
Zeitoun
, and J.
Lüning
, “Laser-induced ultrafast demagnetization in the presence of a nanoscale magnetic domain network
,” Nat. Commun.
3
, 999
(2012
).10.
B.
Pfau
, S.
Schaffert
, L.
Müller
, C.
Gutt
, A.
Al-Shemmary
, F.
Büttner
, R.
Delaunay
, S.
Düsterer
, S.
Flewett
, R.
Frömter
, J.
Geilhufe
, E.
Guehrs
, C. M.
Günther
, R.
Hawaldar
, M.
Hille
, N.
Jaouen
, A.
Kobs
, K.
Li
, J.
Mohanty
, H.
Redlin
, W. F.
Schlotter
, D.
Stickler
, R.
Treusch
, B.
Vodungbo
, M.
Kläui
, H. P.
Oepen
, J.
Lüning
, G.
Grübel
, and S.
Eisebitt
, “Ultrafast optical demagnetization manipulates nanoscale spin structure in domain walls
,” Nat. Commun.
3
, 1100
(2012
).11.
C.-H.
Lambert
, S.
Mangin
, B. S. D. C. S.
Varaprasad
, Y. K.
Takahashi
, M.
Hehn
, M.
Cinchetti
, G.
Malinowski
, K.
Hono
, Y.
Fainman
, M.
Aeschlimann
, and E. E.
Fullerton
, “All-optical control of ferromagnetic thin films and nanostructures
,” Science
345
, 1337
–1340
(2014
).12.
R.
Medapalli
, D.
Afanasiev
, D. K.
Kim
, Y.
Quessab
, S.
Manna
, S. A.
Montoya
, A.
Kirilyuk
, T.
Rasing
, A. V.
Kimel
, and E. E.
Fullerton
, “Multiscale dynamics of helicity-dependent all-optical magnetization reversal in ferromagnetic Co/Pt multilayers
,” Phys. Rev. B
96
, 224421
(2017
).13.
G.
Kichin
, M.
Hehn
, J.
Gorchon
, G.
Malinowski
, J.
Hohlfeld
, and S.
Mangin
, “From multiple- to single-pulse all-optical helicity-dependent switching in ferromagnetic Co/Pt multilayers
,” Phys. Rev. Appl.
12
, 024019
(2019
).14.
G.
Schütz
, S.
Stähler
, M.
Knülle
, P.
Fischer
, S.
Parkin
, and H.
Ebert
, “Distribution of magnetic moments in Co/Pt and Co/Pt/Ir/Pt multilayers detected by magnetic x-ray absorption
,” J. Appl. Phys.
73
, 6430
–6432
(1993
).15.
F.
Wilhelm
, P.
Poulopoulos
, G.
Ceballos
, H.
Wende
, K.
Baberschke
, P.
Srivastava
, D.
Benea
, H.
Ebert
, M.
Angelakeris
, N. K.
Flevaris
, D.
Niarchos
, A.
Rogalev
, and N. B.
Brookes
, “Layer-resolved magnetic moments in multilayers
,” Phys. Rev. Lett.
85
, 413
–416
(2000
).16.
J.
Geissler
, E.
Goering
, M.
Justen
, F.
Weigand
, G.
Schütz
, J.
Langer
, D.
Schmitz
, H.
Maletta
, and R.
Mattheis
, “Pt magnetization profile in a Pt/Co bilayer studied by resonant magnetic x-ray reflectometry
,” Phys. Rev. B
65
, 020405
(2001
).17.
F.
Willems
, C. T. L.
Smeenk
, N.
Zhavoronkov
, O.
Kornilov
, I.
Radu
, M.
Schmidbauer
, M.
Hanke
, C.
von Korff Schmising
, M. J. J.
Vrakking
, and S.
Eisebitt
, “Probing ultrafast spin dynamics with high-harmonic magnetic circular dichroism spectroscopy
,” Phys. Rev. B
92
, 220405
(2015
).18.
M.
Hofherr
, S.
Moretti
, J.
Shim
, S.
Häuser
, N. Y.
Safonova
, M.
Stiehl
, A.
Ali
, S.
Sakshath
, J. W.
Kim
, D. H.
Kim
, H. J.
Kim
, J. I.
Hong
, H. C.
Kapteyn
, M. M.
Murnane
, M.
Cinchetti
, D.
Steil
, S.
Mathias
, B.
Stadtmüller
, M.
Albrecht
, D. E.
Kim
, U.
Nowak
, and M.
Aeschlimann
, “Induced versus intrinsic magnetic moments in ultrafast magnetization dynamics
,” Phys. Rev. B
98
, 174419
(2018
).19.
I.
Vaskivskyi
, R. S.
Malik
, L.
Salemi
, D.
Turenne
, R.
Knut
, J.
Brock
, R.
Stefanuik
, J.
Söderström
, K.
Carva
, E. E.
Fullerton
, P. M.
Oppeneer
, O.
Karis
, and H. A.
Dürr
, “Element-specific magnetization dynamics in Co–Pt alloys induced by strong optical excitation
,” J. Phys. Chem. C
125
, 11714
–11721
(2021
).20.
K.
Yamamoto
, Y.
Kubota
, M.
Suzuki
, Y.
Hirata
, K.
Carva
, M.
Berritta
, K.
Takubo
, Y.
Uemura
, R.
Fukaya
, K.
Tanaka
, W.
Nishimura
, T.
Ohkochi
, T.
Katayama
, T.
Togashi
, K.
Tamasaku
, M.
Yabashi
, Y.
Tanaka
, T.
Seki
, K.
Takanashi
, P. M.
Oppeneer
, and H.
Wadati
, “Ultrafast demagnetization of Pt magnetic moment in L10-FePt probed by magnetic circular dichroism at a hard x-ray free electron laser
,” New J. Phys.
21
, 123010
(2019
).21.
K.
Yamamoto
, S. E.
Moussaoui
, Y.
Hirata
, S.
Yamamoto
, Y.
Kubota
, S.
Owada
, M.
Yabashi
, T.
Seki
, K.
Takanashi
, I.
Matsuda
, and H.
Wadati
, “Element-selectively tracking ultrafast demagnetization process in Co/Pt multilayer thin films by the resonant magneto-optical Kerr effect
,” Appl. Phys. Lett.
116
, 172406
(2020
).22.
M.
Hennes
, B.
Rösner
, V.
Chardonnet
, G. S.
Chiuzbaian
, R.
Delaunay
, F.
Döring
, V. A.
Guzenko
, M.
Hehn
, R.
Jarrier
, A.
Kleibert
et al, “Time-resolved XUV absorption spectroscopy and magnetic circular dichroism at the Ni -edges
,” Appl. Sci.
11
, 325
(2020
).23.
K.
Yao
, F.
Willems
, C.
von Korff Schmising
, I.
Radu
, C.
Strüber
, D.
Schick
, D.
Engel
, A.
Tsukamoto
, J. K.
Dewhurst
, S.
Sharma
, and S.
Eisebitt
, “Distinct spectral response in M-edge magnetic circular dichroism
,” Phys. Rev. B
102
, 100405
(2020
).24.
F.
Willems
, C.
von Korff Schmising
, D.
Weder
, C. M.
Günther
, M.
Schneider
, B.
Pfau
, S.
Meise
, E.
Guehrs
, J.
Geilhufe
, A. E. D.
Merhe
, E.
Jal
, B.
Vodungbo
, J.
Lüning
, B.
Mahieu
, F.
Capotondi
, E.
Pedersoli
, D.
Gauthier
, M.
Manfredda
, and S.
Eisebitt
, “Multi-color imaging of magnetic Co/Pt heterostructures
,” Struct. Dyn.
4
, 014301
(2017
).25.
Slight changes to the laser chirp allow to obtain shorter pulses and, consequently, higher intensities. When playing with the iris aperture, a compromise has to be found: on the one hand, reducing the diameter of the latter increases the beam waist, which allows to generate more photons; on the other hand, one has to deal with a decreasing laser intensity at focus in the gas cell.
26.
J. B.
Kortright
, S.-K.
Kim
, G. P.
Denbeaux
, G.
Zeltzer
, K.
Takano
, and E. E.
Fullerton
, “Soft-x-ray small-angle scattering as a sensitive probe of magnetic and charge heterogeneity
,” Phys. Rev. B
64
, 092401
(2001
).27.
B.
Vodungbo
, A. B.
Sardinha
, J.
Gautier
, G.
Lambert
, M.
Lozano
, S.
Sebban
, E.
Meltchakov
, F.
Delmotte
, V.
Lopez-Flores
, J.
Arabski
, C.
Boeglin
, E.
Beaurepaire
, R.
Delaunay
, J.
Lüning
, and P.
Zeitoun
, “Table-top resonant magnetic scattering with extreme ultraviolet light from high-order harmonic generation
,” Europhys. Lett.
94
, 54003
(2011
).28.
V.
Cardin
, T.
Balciunas
, K.
Légaré
, A.
Baltuska
, H.
Ibrahim
, E.
Jal
, B.
Vodungbo
, N.
Jaouen
, C.
Varin
, J.
Lüning
, and F.
Légaré
, “Wavelength scaling of ultrafast demagnetization in Co/Pt multilayers
,” Phys. Rev. B
101
, 054430
(2020
).29.
M.
Hennes
, A.
Merhe
, X.
Liu
, D.
Weder
, C. v K.
Schmising
, M.
Schneider
, C. M.
Günther
, B.
Mahieu
, G.
Malinowski
, M.
Hehn
, D.
Lacour
, F.
Capotondi
, E.
Pedersoli
, I. P.
Nikolov
, V.
Chardonnet
, E.
Jal
, J.
Lüning
, and B.
Vodungbo
, “Laser-induced ultrafast demagnetization and perpendicular magnetic anisotropy reduction in a Co88Tb12 thin film with stripe domains
,” Phys. Rev. B
102
, 174437
(2020
).30.
G.
van der Laan
, “Soft X-ray resonant magnetic scattering of magnetic nanostructures
,” C. R. Phys.
9
, 570
–584
(2008
).31.
C.
Alves
, G.
Lambert
, V.
Malka
, M.
Hehn
, G.
Malinowski
, M.
Hennes
, V.
Chardonnet
, E.
Jal
, J.
Lüning
, and B.
Vodungbo
, “Resonant faraday effect using high-order harmonics for the investigation of ultrafast demagnetization
,” Phys. Rev. B
100
, 144421
(2019
).32.
J. K.
Dewhurst
, F.
Willems
, P.
Elliott
, Q. Z.
Li
, C. v K.
Schmising
, C.
Strüber
, D. W.
Engel
, S.
Eisebitt
, and S.
Sharma
, “Element specificity of transient extreme ultraviolet magnetic dichroism
,” Phys. Rev. Lett.
124
, 077203
(2020
).33.
E.
Beaurepaire
, J.-C.
Merle
, A.
Daunois
, and J.-Y.
Bigot
, “Ultrafast spin dynamics in ferromagnetic nickel
,” Phys. Rev. Lett.
76
, 4250
–4253
(1996
).34.
S.
Mathias
, C.
La-O-Vorakiat
, P.
Grychtol
, P.
Granitzka
, E.
Turgut
, J. M.
Shaw
, R.
Adam
, H. T.
Nembach
, M. E.
Siemens
, S.
Eich
, C. M.
Schneider
, T. J.
Silva
, M.
Aeschlimann
, M. M.
Murnane
, and H. C.
Kapteyn
, “Probing the timescale of the exchange interaction in a ferromagnetic alloy
,” Proc. Natl. Acad. Sci.
109
, 4792
–4797
(2012
).35.
S.
Jana
, R.
Knut
, S.
Muralidhar
, R. S.
Malik
, R.
Stefanuik
, J.
Åkerman
, O.
Karis
, C.
Schüßler-Langeheine
, and N.
Pontius
, “Experimental confirmation of the delayed Ni demagnetization in FeNi alloy
,” arXiv:2106.07956 (2021
).© 2022 Author(s). Published under an exclusive license by AIP Publishing.
2022
Author(s)
You do not currently have access to this content.