Ultrafast Dynamics of Demagnetization in FeMn/MnGa Bilayer Nanofilm Structures Via Phonon Transport

Overview

Journal Nanomaterials (Basel)

Date 2022 Nov 26

PMID 36432373

Authors

Tianran Jiang

Xupeng Zhao

Zhifeng Chen

Yongyong You

Tianshu Lai

Jianhua Zhao

Affiliations

Soon will be listed here.

Abstract

Superdiffusive spin transport has been proposed as a new mechanism of ultrafast demagnetization in layered magnetic nanostructures and demonstrated experimentally. However, it is unknown if it is possible for phonon transport to occur and manipulate ultrafast demagnetization. Here, we explore the ultrafast dynamics of demagnetization of an antiferromagnet/ferromagnet bilayer nanostructure, of a FeMn/MnGa bilayer film prepared by molecular beam epitaxy. Ultrafast dynamics of a two-step demagnetization were observed through the time-resolved magneto-optical Kerr effect. The first-step fast component of the two-step demagnetization occurred within ~200 fs, while the second-step slow component emerged in a few tens of picoseconds. For a single MnGa film, only the ultrafast dynamics of the first-step fast demagnetization were observed, revealing that the second-step slow demagnetization originates from interlayer phonon transport. A four-temperature model considering phonon transport was developed and used to effectively reproduce the observed ultrafast dynamics of two-step demagnetization. Our results reveal the effect of phonon transport on demagnetization for the first time and open up a new route to manipulate ultrafast demagnetization in layered magnetic structures.

Citing Articles

Fluence and Temperature Dependences of Laser-Induced Ultrafast Demagnetization and Recovery Dynamics in 1-FePt Thin Film.

Xie Z, Cai Y, Tang M, Zhou J, Liu J, Peng J Materials (Basel). 2023; 16(14).

PMID: 37512360 PMC: 10385860. DOI: 10.3390/ma16145086.

References

Radu I, Vahaplar K, Stamm C, Kachel T, Pontius N, Durr H . Transient ferromagnetic-like state mediating ultrafast reversal of antiferromagnetically coupled spins. Nature. 2011; 472(7342):205-8. DOI: 10.1038/nature09901. View

Bergeard N, Hehn M, Mangin S, Lengaigne G, Montaigne F, Lalieu M . Hot-Electron-Induced Ultrafast Demagnetization in Co/Pt Multilayers. Phys Rev Lett. 2016; 117(14):147203. DOI: 10.1103/PhysRevLett.117.147203. View

Beyazit Y, Beckord J, Zhou P, Meyburg J, Kuhne F, Diesing D . Local and Nonlocal Electron Dynamics of Au/Fe/MgO(001) Heterostructures Analyzed by Time-Resolved Two-Photon Photoemission Spectroscopy. Phys Rev Lett. 2020; 125(7):076803. DOI: 10.1103/PhysRevLett.125.076803. View

Zhang W, Jungfleisch M, Jiang W, Pearson J, Hoffmann A, Freimuth F . Spin Hall effects in metallic antiferromagnets. Phys Rev Lett. 2014; 113(19):196602. DOI: 10.1103/PhysRevLett.113.196602. View

Turgut E, La-O-Vorakiat C, Shaw J, Grychtol P, Nembach H, Rudolf D . Controlling the competition between optically induced ultrafast spin-flip scattering and spin transport in magnetic multilayers. Phys Rev Lett. 2013; 110(19):197201. DOI: 10.1103/PhysRevLett.110.197201. View

Bonfiglio G, Rode K, Atcheson G, Stamenov P, Coey J, Kimel A . Sub-picosecond exchange-relaxation in the compensated ferrimagnet MnRuGa. J Phys Condens Matter. 2021; 33(13). DOI: 10.1088/1361-648X/abda7c. View

Koopmans B, Malinowski G, Dalla Longa F, Steiauf D, Fahnle M, Roth T . Explaining the paradoxical diversity of ultrafast laser-induced demagnetization. Nat Mater. 2009; 9(3):259-65. DOI: 10.1038/nmat2593. View

Melnikov A, Razdolski I, Wehling T, Papaioannou E, Roddatis V, Fumagalli P . Ultrafast transport of laser-excited spin-polarized carriers in Au/Fe/MgO(001). Phys Rev Lett. 2011; 107(7):076601. DOI: 10.1103/PhysRevLett.107.076601. View

Guidoni L, Beaurepaire E, Bigot J . Magneto-optics in the ultrafast regime: thermalization of spin populations in ferromagnetic films. Phys Rev Lett. 2002; 89(1):017401. DOI: 10.1103/PhysRevLett.89.017401. View

10.

Wang Z, Li J, Deng J, Chen Z, Lai T . Synchronized time- and high-field-resolved all-optical pump-probe magneto-optical setup based on a strong alternating magnetic field and its application in magnetization dynamics of high coercivity magnetic medium. Rev Sci Instrum. 2011; 82(3):034703. DOI: 10.1063/1.3565156. View

11.

Battiato M, Carva K, Oppeneer P . Superdiffusive spin transport as a mechanism of ultrafast demagnetization. Phys Rev Lett. 2010; 105(2):027203. DOI: 10.1103/PhysRevLett.105.027203. View

12.

Muller G, Walowski J, Djordjevic M, Miao G, Gupta A, Ramos A . Spin polarization in half-metals probed by femtosecond spin excitation. Nat Mater. 2008; 8(1):56-61. DOI: 10.1038/nmat2341. View

13.

Shokeen V, Sanchez Piaia M, Bigot J, Muller T, Elliott P, Dewhurst J . Spin Flips versus Spin Transport in Nonthermal Electrons Excited by Ultrashort Optical Pulses in Transition Metals. Phys Rev Lett. 2017; 119(10):107203. DOI: 10.1103/PhysRevLett.119.107203. View

14.

Seixas T, Salgueiro da Silva M, Lima O, Lopez J, Braun H, Eska G . Specific heat of Gd₄Co₃. J Phys Condens Matter. 2011; 22(13):136002. DOI: 10.1088/0953-8984/22/13/136002. View

15.

Eschenlohr A, Battiato M, Maldonado P, Pontius N, Kachel T, Holldack K . Ultrafast spin transport as key to femtosecond demagnetization. Nat Mater. 2013; 12(4):332-6. DOI: 10.1038/nmat3546. View

16.

Rudolf D, La-O-Vorakiat C, Battiato M, Adam R, Shaw J, Turgut E . Ultrafast magnetization enhancement in metallic multilayers driven by superdiffusive spin current. Nat Commun. 2012; 3:1037. DOI: 10.1038/ncomms2029. View

17.

Mizukami S, Wu F, Sakuma A, Walowski J, Watanabe D, Kubota T . Long-lived ultrafast spin precession in manganese alloys films with a large perpendicular magnetic anisotropy. Phys Rev Lett. 2011; 106(11):117201. DOI: 10.1103/PhysRevLett.106.117201. View

18.

BEAUREPAIRE , MERLE , Daunois , Bigot . Ultrafast spin dynamics in ferromagnetic nickel. Phys Rev Lett. 1996; 76(22):4250-4253. DOI: 10.1103/PhysRevLett.76.4250. View