Marwan Deb
Current Organizations / Institutes
The organizations/institutes from the scholar's latest article
Previous Organizations / Institutes
The organizations / institutes from the scholar's other articles in the past ten years
Research Subjects
Research Interests
Marwan Deb has a total of 109 co-authors. Here are the top co-authors by number of shared publications:
- Elena Popova
Institut de Physique de Rennes (IPR)
12 shared publications Niels Keller
Institut de Physique de Rennes (IPR), CNRS, UMR6251–Université de Rennes, 35000 Rennes, France
12 shared publicationsMatias Bargheer
University of Potsdam
7 shared publicationsElena Popova
Institut de Physique de Rennes (IPR), CNRS, UMR6251–Université de Rennes, 35000 Rennes, France
5 shared publicationsMichel Hehn
Institut Jean Lamour (IJL)
5 shared publicationsBernard Barbara
CNRS, Institut NEEL, F-38042 Grenoble, France
4 shared publications
Latest Publications
- 25 February 2026
- Published by American Physical Society (APS) in Physical Review Letters
- Vol. 136 (17) , 176701
Spin waves excited by hard x-ray transient gratings
Recent progress in ultrafast x-ray sources helped establish x-rays as an important tool for probing lattice and magnetic dynamics initiated by femtosecond optical pulses. Here, we explore the potential of ultrashort hard x-ray pulses for driving magnetic dynamics. We use a transient grating technique in which a spatially periodic x-ray excitation pattern gives rise to material excitations at a well-defined wave vector, whose dynamics are monitored via diffraction of an optical probe pulse. The excitation of a ferrimagnetic gadolinium bismuth iron garnet film placed in an external tilted magnetic field by x-rays at the Gd L_{3} edge results in both magnetic and nonmagnetic transient gratings whose contributions to the diffracted signal are separated by polarization analysis. We observe the magnetization precession at both longitudinal acoustic and spin wave frequencies. An analysis with the Landau-Lifshitz-Gilbert equation indicates that the magnetization precession is driven by strain resulting from thermal expansion induced by absorbed x-rays. The results establish x-ray transient gratings as a tool for driving coherent phonons and magnons, with the potential of accessing wave vectors across the entire Brillouin zone.
- 25 February 2026
- Published by American Physical Society (APS) in Physical Review Letters
- Vol. 136 (17) , 176701
Spin waves excited by hard x-ray transient gratings
Recent progress in ultrafast x-ray sources helped establish x-rays as an important tool for probing lattice and magnetic dynamics initiated by femtosecond optical pulses. Here, we explore the potential of ultrashort hard x-ray pulses for driving magnetic dynamics. We use a transient grating technique in which a spatially periodic x-ray excitation pattern gives rise to material excitations at a well-defined wave vector, whose dynamics are monitored via diffraction of an optical probe pulse. The excitation of a ferrimagnetic gadolinium bismuth iron garnet film placed in an external tilted magnetic field by x-rays at the Gd L_{3} edge results in both magnetic and nonmagnetic transient gratings whose contributions to the diffracted signal are separated by polarization analysis. We observe the magnetization precession at both longitudinal acoustic and spin wave frequencies. An analysis with the Landau-Lifshitz-Gilbert equation indicates that the magnetization precession is driven by strain resulting from thermal expansion induced by absorbed x-rays. The results establish x-ray transient gratings as a tool for driving coherent phonons and magnons, with the potential of accessing wave vectors across the entire Brillouin zone.
- 26 September 2025
- Published by American Physical Society (APS) in Physical Review Applied
- Vol. 24 (3)
Energy-efficient generation of high-frequency spin waves in /Co-based heterostructures using laser pulses- 26 September 2025
- Published by American Physical Society (APS) in Physical Review Applied
- Vol. 24 (3)
Energy-efficient generation of high-frequency spin waves in /Co-based heterostructures using laser pulses- 17 November 2022
- Published by American Physical Society (APS) in Physical Review B
- Vol. 106 (18) , 184416
Polarization-dependent subpicosecond demagnetization in iron garnets
Controlling the magnetization dynamics at the fastest speed is a major issue of fundamental condensed matter physics and its applications for data storage and processing technologies. It requires a deep understanding of the interactions between the degrees of freedom in solids, such as spin, electron, and lattice as well as their responses to external stimuli. In this paper, we systematically investigate the fluence dependence of ultrafast magnetization dynamics induced by below-bandgap ultrashort laser pulses in the ferrimagnetic insulators with . We demonstrate subpicosecond demagnetization dynamics in this material followed by a very slow remagnetization process. We prove that this demagnetization results from an ultrafast heating of iron garnets by two-photon absorption (TPA), suggesting a phonon-magnon thermalization time of ps. We explain the slow remagnetization timescale by the low phonon heat conductivity in garnets. Additionally, we show that the amplitudes of the demagnetization, optical change, and lattice strain can be manipulated by changing the ellipticity of the pump pulses. We explain this phenomenon considering the TPA circular dichroism. These findings open exciting prospects for ultrafast manipulation of spin, charge, and lattice dynamics in magnetic insulators by ultrafast nonlinear optics.- 17 November 2022
- Published by American Physical Society (APS) in Physical Review B
- Vol. 106 (18) , 184416
Polarization-dependent subpicosecond demagnetization in iron garnets
Controlling the magnetization dynamics at the fastest speed is a major issue of fundamental condensed matter physics and its applications for data storage and processing technologies. It requires a deep understanding of the interactions between the degrees of freedom in solids, such as spin, electron, and lattice as well as their responses to external stimuli. In this paper, we systematically investigate the fluence dependence of ultrafast magnetization dynamics induced by below-bandgap ultrashort laser pulses in the ferrimagnetic insulators with . We demonstrate subpicosecond demagnetization dynamics in this material followed by a very slow remagnetization process. We prove that this demagnetization results from an ultrafast heating of iron garnets by two-photon absorption (TPA), suggesting a phonon-magnon thermalization time of ps. We explain the slow remagnetization timescale by the low phonon heat conductivity in garnets. Additionally, we show that the amplitudes of the demagnetization, optical change, and lattice strain can be manipulated by changing the ellipticity of the pump pulses. We explain this phenomenon considering the TPA circular dichroism. These findings open exciting prospects for ultrafast manipulation of spin, charge, and lattice dynamics in magnetic insulators by ultrafast nonlinear optics.- 3 October 2022
- Published by American Physical Society (APS) in Physical Review Applied
- Vol. 18 (4) , 044001
Controlling High-Frequency Spin-Wave Dynamics Using Double-Pulse Laser Excitation
Manipulating spin waves is highly required for the development of innovative data transport and processing technologies. Recently, the possibility of triggering high-frequency standing spin waves in magnetic insulators using femtosecond laser pulses was discovered, raising the question about how one can manipulate their dynamics. Here we explore this question by investigating the ultrafast magnetization and spin-wave dynamics induced by double-pulse laser excitation. We demonstrate a suppression or enhancement of the amplitudes of the standing spin waves by precisely tuning the time delay between the two pulses. The results can be understood as the constructive or destructive interference of the spin waves induced by the first and second laser pulses. Our findings open exciting perspectives towards generating single-mode standing spin waves that combine high frequency with large amplitude and low magnetic damping.
- 3 October 2022
- Published by American Physical Society (APS) in Physical Review Applied
- Vol. 18 (4) , 044001
Controlling High-Frequency Spin-Wave Dynamics Using Double-Pulse Laser Excitation
Manipulating spin waves is highly required for the development of innovative data transport and processing technologies. Recently, the possibility of triggering high-frequency standing spin waves in magnetic insulators using femtosecond laser pulses was discovered, raising the question about how one can manipulate their dynamics. Here we explore this question by investigating the ultrafast magnetization and spin-wave dynamics induced by double-pulse laser excitation. We demonstrate a suppression or enhancement of the amplitudes of the standing spin waves by precisely tuning the time delay between the two pulses. The results can be understood as the constructive or destructive interference of the spin waves induced by the first and second laser pulses. Our findings open exciting perspectives towards generating single-mode standing spin waves that combine high frequency with large amplitude and low magnetic damping.
- 26 January 2022
- Published by American Physical Society (APS) in Physical Review B
- Vol. 105 (1) , 014432
Magnetic damping of ferromagnetic and exchange resonance modes in a ferrimagnetic insulator
Understanding the damping is an important fundamental problem with widespread implications in magnetic technology. Ferrimagnetic materials offer a rich platform to explore not only the damping of the ferromagnetic mode, but also the damping of the high-frequency exchange mode very promising for ultrafast devices. Here we use time-resolved magneto-optical Kerr effect to investigate the ferromagnetic and exchange resonance modes and their damping in the bismuth-doped gadolinium iron garnet over a broad range of magnetic fields (0–10 T) and temperatures (50–300 K) including the magnetization and angular compensation points. These two resonance modes are excited via the inverse Faraday effect and unambiguously identified by their distinct frequency dependence on temperature and magnetic field. The temperature-dependent measurements in the external magnetic field revealed that the intrinsic damping of the ferromagnetic mode is always smaller than the one of the exchange modes and both have a maximum near the angular compensation point. These results are fully consistent with recent predictions of atomistic simulations and a theory based on two-sublattice Landau-Lifshitz-Bloch equation. We also demonstrate that the damping of these modes varies differently as a function of . We explain the observed behaviors by considering the different features of the effective fields defining the precession frequencies of the ferromagnetic and exchange modes.- 26 January 2022
- Published by American Physical Society (APS) in Physical Review B
- Vol. 105 (1) , 014432
Magnetic damping of ferromagnetic and exchange resonance modes in a ferrimagnetic insulator
Understanding the damping is an important fundamental problem with widespread implications in magnetic technology. Ferrimagnetic materials offer a rich platform to explore not only the damping of the ferromagnetic mode, but also the damping of the high-frequency exchange mode very promising for ultrafast devices. Here we use time-resolved magneto-optical Kerr effect to investigate the ferromagnetic and exchange resonance modes and their damping in the bismuth-doped gadolinium iron garnet over a broad range of magnetic fields (0–10 T) and temperatures (50–300 K) including the magnetization and angular compensation points. These two resonance modes are excited via the inverse Faraday effect and unambiguously identified by their distinct frequency dependence on temperature and magnetic field. The temperature-dependent measurements in the external magnetic field revealed that the intrinsic damping of the ferromagnetic mode is always smaller than the one of the exchange modes and both have a maximum near the angular compensation point. These results are fully consistent with recent predictions of atomistic simulations and a theory based on two-sublattice Landau-Lifshitz-Bloch equation. We also demonstrate that the damping of these modes varies differently as a function of . We explain the observed behaviors by considering the different features of the effective fields defining the precession frequencies of the ferromagnetic and exchange modes.- 27 May 2021
- Published by American Physical Society (APS) in Physical Review Applied
- Vol. 15 (5) , 054064
Tunable Exchange-Bias-Like Effect in -Substituted Gadolinium Iron Garnet FilmUsing magneto-optical Faraday and Kerr measurements, we investigate the magnetic and magneto-optical properties of a thick -substituted gadolinium iron garnet film over a broad range of wavelengths (250–850 nm) and temperatures (150–300 K), including the magnetization compensation point, . We observe an exchange-bias-like effect in the vicinity of . By slightly changing the sample temperature, we can precisely tune the bias field, which reaches a magnitude 6 times higher than the coercive field. We explain this phenomenon by considering the short-range superexchange interaction and a change in the magnetic behavior when moving from the surface to the bulk of the film. This finding may lead to the development of single-film magneto-optical devices based on the exchange-bias effect.- 27 May 2021
- Published by American Physical Society (APS) in Physical Review Applied
- Vol. 15 (5) , 054064
Tunable Exchange-Bias-Like Effect in -Substituted Gadolinium Iron Garnet FilmUsing magneto-optical Faraday and Kerr measurements, we investigate the magnetic and magneto-optical properties of a thick -substituted gadolinium iron garnet film over a broad range of wavelengths (250–850 nm) and temperatures (150–300 K), including the magnetization compensation point, . We observe an exchange-bias-like effect in the vicinity of . By slightly changing the sample temperature, we can precisely tune the bias field, which reaches a magnitude 6 times higher than the coercive field. We explain this phenomenon by considering the short-range superexchange interaction and a change in the magnetic behavior when moving from the surface to the bulk of the film. This finding may lead to the development of single-film magneto-optical devices based on the exchange-bias effect.- 1 February 2021
- Published by American Physical Society (APS) in Physical Review B
- Vol. 103 (6) , 064301
Ultrafast control of lattice strain via magnetic circular dichroism
Using ultrafast x-ray diffraction, we directly monitor the lattice dynamics induced by femtosecond laser pulses in nanoscale thin films of bismuth iron garnet in external magnetic fields . We control the ultrafast laser-induced lattice strain amplitude by changing the laser pulse helicity. The strength of is used as an external parameter to switch the helicity dependence on and off, respectively. Based on magneto-optical spectroscopic measurements, we explain these phenomena by magnetic circular dichroism. Our findings highlight an important approach for ultrafast manipulation of lattice strain in magnetic materials, in particular insulators, and open exciting perspectives towards ultrafast control of lattice strain and heat-induced magnetization switching and spin waves in bismuth substituted iron garnets using the polarization of light.- 1 February 2021
- Published by American Physical Society (APS) in Physical Review B
- Vol. 103 (6) , 064301
Ultrafast control of lattice strain via magnetic circular dichroism
Using ultrafast x-ray diffraction, we directly monitor the lattice dynamics induced by femtosecond laser pulses in nanoscale thin films of bismuth iron garnet in external magnetic fields . We control the ultrafast laser-induced lattice strain amplitude by changing the laser pulse helicity. The strength of is used as an external parameter to switch the helicity dependence on and off, respectively. Based on magneto-optical spectroscopic measurements, we explain these phenomena by magnetic circular dichroism. Our findings highlight an important approach for ultrafast manipulation of lattice strain in magnetic materials, in particular insulators, and open exciting perspectives towards ultrafast control of lattice strain and heat-induced magnetization switching and spin waves in bismuth substituted iron garnets using the polarization of light.- 11 January 2021
- Published by American Physical Society (APS) in Physical Review B
- Vol. 103 (2) , 024411
Generation of spin waves via spin-phonon interaction in a buried dielectric thin film
In this paper, we investigate the magnetic, optical, and lattice responses of a heterostructure to femtosecond laser excitation of the opaque Pt/Cu metallic bilayer. The electronic excitation generates coherent and incoherent phonons, which trigger high-frequency standing spin waves (SWs) in the dielectric layer via a phonon-induced change of magnetic anisotropy. We find that the incoherent phonons (heat) can induce a fast and slow decrease of the magnetic order by different spin-phonon interaction scenarios. These results open perspectives for generating high-frequency SWs in buried magnetic garnets.- 11 January 2021
- Published by American Physical Society (APS) in Physical Review B
- Vol. 103 (2) , 024411
Generation of spin waves via spin-phonon interaction in a buried dielectric thin film
In this paper, we investigate the magnetic, optical, and lattice responses of a heterostructure to femtosecond laser excitation of the opaque Pt/Cu metallic bilayer. The electronic excitation generates coherent and incoherent phonons, which trigger high-frequency standing spin waves (SWs) in the dielectric layer via a phonon-induced change of magnetic anisotropy. We find that the incoherent phonons (heat) can induce a fast and slow decrease of the magnetic order by different spin-phonon interaction scenarios. These results open perspectives for generating high-frequency SWs in buried magnetic garnets.- Open Access
- 13 April 2020
- Published by American Physical Society (APS) in Physical Review Research
- Vol. 2 (2) , 022013
Measurement of transient strain induced by two-photon excitation
By ultrafast x-ray diffraction we quantify the strain from coherent and incoherent phonons generated by one- and two-photon absorption. We investigated the ferrimagnetic insulator bismuth-doped yttrium iron garnet, which is a workhorse for laser-induced spin dynamics that may be excited indirectly via phonons. We identify the two-photon absorption by the quadratic intensity dependence of the transient strain and confirm a short lifetime of the intermediate state via the inverse proportional dependence on the pump-pulse duration. We determine the two-photon absorption coefficient using the linear relation between strain and absorbed energy density. For large intensities of about considerable strain amplitudes of 0.1% are driven exclusively by two-photon absorption.- 13 April 2020
- Published by American Physical Society (APS) in Physical Review Research
- Vol. 2 (2) , 022013
Open AccessMeasurement of transient strain induced by two-photon excitation
By ultrafast x-ray diffraction we quantify the strain from coherent and incoherent phonons generated by one- and two-photon absorption. We investigated the ferrimagnetic insulator bismuth-doped yttrium iron garnet, which is a workhorse for laser-induced spin dynamics that may be excited indirectly via phonons. We identify the two-photon absorption by the quadratic intensity dependence of the transient strain and confirm a short lifetime of the intermediate state via the inverse proportional dependence on the pump-pulse duration. We determine the two-photon absorption coefficient using the linear relation between strain and absorbed energy density. For large intensities of about considerable strain amplitudes of 0.1% are driven exclusively by two-photon absorption.