Accelerating the laser-induced demagnetization of a ferromagnetic film by antiferromagnetic order in an adjacent layer

Kumberg, Ivar; Golias, E.; Pontius, N.; Hosseinifar, Rahil; Frischmuth, Karl; Gelen, I.; Shinwari, Tauqir; Thakur, Sangeeta; Schüßler-Langeheine, C.; Oppeneer, Peter M.; Kuch, W.

doi:10.1103/physrevb.102.214418

Cited by 7 publications

(6 citation statements)

References 50 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…For the NiMn composition of Ni 31 Mn 69 and the thickness of 20 ML, the antiferromagnetic ordering temperature of NiMn can be estimated to about 360 K [33,36,49]. Above its ordering temperature, the NiMn layer does not influence the Co layer magnetically [36], but the presence of the additional layer and of exchange-coupled magnetic moments at the interface to the Co layer may be influential via transient nonlocal effects such as the interchange or the reflection of electronic spin currents at the Co/NiMn interface [15]. However, from the comparison to the existing results on Co/Cu(001) from literature mentioned above, a significant role of the additional interface between Co and the magnetically disordered NiMn layer for the ultrafast dynamics of the Co layer can not be discerned.…”

Section: Resultsmentioning

confidence: 99%

“…Such studies are essential for the understanding of ultrafast magnetization dynamics and have led to substantial insight into the underlying physical mechanisms and their theoretical description, such as, for example, the microscopic three-temperature model [6]. Combining ultrashort soft-x-ray probe pulses with near-infrared pump pulses to follow the magnetic response of an excited system [7][8][9][10][11][12][13][14][15][16] contributes an invaluable method to this field to meet the high demands of time-and element-resolved studies of ultrafast magnetism. It is particularly the elemental resolution of this approach that has helped to identify the role of the different timescales of demagnetization of 3d and 4f elements in ferrimagnetic alloys for the ultrafast laser-induced alloptical magnetic switching [10], prove the presence of nonlocal spin transport in ultrafast demagnetization [11], and has led to a number of investigations disentangling the complex evolution of the magnetic system, spin and electron scattering, as well as transport upon intense optical excitation [10,11,13,16].…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Ultrafast laser-induced magneto-optical changes in resonant magnetic x-ray reflectivity

Kumberg,

Golias,

Hadjadj

et al. 2023

Phys. Rev. B

Self Cite

View full text Add to dashboard Cite

We investigate the magneto-optical response of Co to an ultrashort laser excitation by x-ray resonant magnetic reflectivity (XRMR) employing circular polarization. The time-resolved reflectivities detected for opposite sample magnetization are separated into magnetic and nonmagnetic contributions, which contain information about the structural, electronic, and magnetic properties of the sample. Different response times of the different contributions are observed. The experimental results are reproduced numerically by two different simulation approaches. On the one hand, we use a purely thermal model, a time-dependent heat-induced loss of macroscopic magnetization, and an inhomogeneous laser-induced strain profile. On the other hand, we employ time-dependent densityfunctional theory to calculate the transient optical response to the laser-induced excitation and from that the reflected intensities. While both methods are able to reproduce the time dependence of the magnetic signal, the ultrafast nonmagnetic change in reflectivity is captured satisfactorily only in simulations of the transient optical response function and has thus to be assigned to electronic effects. The energy dependence of the magnetic circular dichroism is investigated in the simulations, highlighting a dependence of the observable on the probing energy. Finally, a phenomenological explanation of the dynamics measured in dichroic x-ray reflectivity in the different channels is offered.

show abstract

Section: Resultsmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Ultrafast laser-induced magneto-optical changes in resonant magnetic x-ray reflectivity

Kumberg,

Golias,

Hadjadj

et al. 2023

Phys. Rev. B

Self Cite

View full text Add to dashboard Cite

show abstract

“…[21] In the meantime, the exchange bias of the Co/IrMn interface is only affected by laser heating and the interacted AFM spin configuration itself. [27] In Fig. 3, we can note that the maximum amplitude of the exchange bias switching at the IrMn/CoGd interface decreases with the increased IrMn thickness.…”

Section: Laser-induced Ultrafast Antiferromagnet Rearrangementmentioning

confidence: 86%

Ultrafast antiferromagnet rearrangement in Co/IrMn/CoGd trilayers

et al. 2023

View full text Add to dashboard Cite

Antiferromagnets offer great potential for high-speed data processing applications, as they can lead spintronic devices from a static storage and gigahertz frequency range to the terahertz range. However, their zero net magnetization makes them difficult to manipulate and detect. In recent years, there has been a lot of attention given to the ultrafast manipulation of magnetic order using ultra-short single laser pulses, but it remains unknown whether a similar scenario can be observed in antiferromagnets. In this work, we demonstrate the manipulation of antiferromagnets with a single femtosecond laser pulse in perpendicular exchange-biased Co/IrMn/CoGd trilayers. We studied the dual exchange bias interlayer interaction in quasi-static conditions and competition in ultrafast antiferromagnet rearrangement. Our results show that, compared to conventional ferromagnetic/antiferromagnetic systems, the IrMn antiferromagnet can be ultrafast and efficiently manipulated by the coupled CoGd ferrimagnetic layer, which paves the way for potential energy-efficient spintronic devices.

show abstract

“…Several reports have suggested that photoexcitation of the AFM/FM interface induces significant modulations in the exchange bias field on ultrashort timescales. [17][18][19] Detailed time-resolved studies of dynamics showed that the characteristic timescale of laserinduced exchange bias quenching in a polycrystalline Co/IrMn bilayer is 0.7 ± 0.5 ps, attributing the rapid decrease in exchange coupling to a spin disorder at the interface created by laser heating. [17] In our case, the demagnetization and switching dynamics after a 40 fs laser pulse illumination of the annealed IrMn(5)/Co 77 Gd 23 (4) sample have been studied as a function of time for various laser fluences (Figure 3a) and for different applied fields intensities (Figure 3b).…”

Section: Exchange Bias Switchingmentioning

confidence: 99%

Single‐Shot Laser‐Induced Switching of an Exchange Biased Antiferromagnet

Guo,

Wang,

Malinowski

et al. 2024

Advanced Materials

View full text Add to dashboard Cite

Ultrafast manipulation of magnetic order has challenged our understanding the fundamental and dynamic properties of magnetic materials. So far single shot magnetic switching has been limited to ferrimagnetic alloys, multilayers and designed ferromagnetic heterostructures. In ferromagnetic (FM)/antiferromagnetic (AFM) bilayers, exchange bias (He) arises from the interfacial exchange coupling between the two layers and reflects the microscopic orientation of the antiferromagnet. Here we demonstrate the possibility of single shot switching of the antiferromagnet (change of the sign and amplitude of He) with a single femtosecond laser pulse in IrMn/CoGd bilayers. We demonstrate the manipulation in a wide range of fluences for different layer thicknesses and compositions. Atomistic simulations predict ultrafast switching and recovery of the AFM magnetization on a timescale of 2 ps. Our results provide the fastest and the most energy‐efficient method to set the exchange bias and pave the way to potential applications for ultrafast spintronic devices.This article is protected by copyright. All rights reserved

show abstract

Accelerating the laser-induced demagnetization of a ferromagnetic film by antiferromagnetic order in an adjacent layer

Cited by 7 publications

References 50 publications

Ultrafast laser-induced magneto-optical changes in resonant magnetic x-ray reflectivity

Ultrafast laser-induced magneto-optical changes in resonant magnetic x-ray reflectivity

Ultrafast antiferromagnet rearrangement in Co/IrMn/CoGd trilayers

Single‐Shot Laser‐Induced Switching of an Exchange Biased Antiferromagnet

Contact Info

Product

Resources

About