A5070006294- Magnetic properties of thin films
- Magneto-Optical Properties and Applications
- Multiferroics and related materials
- Magnetic Properties and Applications
- Mechanical and Optical Resonators
- Magnetic and transport properties of perovskites and related materials
- Physics of Superconductivity and Magnetism
- Photorefractive and Nonlinear Optics
- Advanced Condensed Matter Physics
- Quantum and electron transport phenomena
- Photoacoustic and Ultrasonic Imaging
- Semiconductor Quantum Structures and Devices
- Transition Metal Oxide Nanomaterials
- Ferroelectric and Piezoelectric Materials
- Photonic and Optical Devices
- Ga2O3 and related materials
- Terahertz technology and applications
- Atomic and Subatomic Physics Research
- Crystal Structures and Properties
- Topological Materials and Phenomena
- Crystallography and Radiation Phenomena
- Magnetic Properties and Synthesis of Ferrites
- Laser-Matter Interactions and Applications
- Geophysics and Sensor Technology
- Photonic Crystals and Applications
Ioffe Institute
2016-2025
Russian Academy of Sciences
2003-2024
ITMO University
2020
The University of Tokyo
2018
Physico-Technical Institute
2003-2017
Radboud University Nijmegen
2006-2010
Using time-resolved single-shot pump-probe microscopy we unveil the mechanism and time scale of all-optical magnetization reversal by a single circularly polarized 100 fs laser pulse. We demonstrate that has linear character, i.e., does not involve precession but occurs via strongly nonequilibrium state. Calculations show which can be achieved this is within 10 ps for 30 nm domain. two subpicosecond pulses 5 microm domain magnetic information recorded readout ps, fastest "write-read" event...
The optical response of the technologically interesting multiferroic ${\text{BiFeO}}_{3}$ and related complex iron oxides, having high N\'eel or Curie temperature, is studied in wide spectral range from 0.6 up to 5.8 eV by means spectroscopic ellipsometry. investigated oxides have different crystal symmetry with ${\text{FeO}}_{6}$ octahedral ${\text{FeO}}_{4}$ tetrahedral centers distorted a certain degree. One two groups materials includes ${\text{BiFeO}}_{3}$, ${\text{ErFeO}}_{3}$,...
Polarization-dependent excitation of coherent spin precession by 150 fs linearly polarized laser pulses is observed in the easy-plane antiferromagnet FeBO3. We show that mechanism impulsive stimulated Raman scattering. This process shown to be determined not only magneto-optical constants material, but also properties itself. Though carrying no angular momentum, act on spins as effective fields can considered an ultrafast inverse Cotton-Mouton effect.
Ultrafast heating of a ferrimagnet’s crystal lattice leads to new state matter with hot spins yet unchanged magnetization.
Time-resolved magneto-optical imaging of laser-excited rare-earth orthoferrite (SmPr)FeO3 demonstrates that a single 60 fs circularly polarized laser pulse is capable creating magnetic domain on picosecond time scale with magnetization direction determined by the helicity light. Depending light intensity and sample temperature, pulses same can create domains opposite magnetizations. We argue this phenomenon relies twofold effect which (i) instantaneously excites coherent low-amplitude spin...
Coherent magnons and phonons are excited by subpicosecond laser pulses in the weak ferromagnet ${\text{FeBO}}_{3}$. Impulsive stimulated Raman scattering (ISRS) is proven to be microscopic mechanism of excitation. It shown that coherent can both linearly circularly polarized where efficiency process depends on mutual orientation magnetic crystallographic axes light propagation direction. The strong ellipticity ferromagnetic magnon mode demonstrated, experimentally theoretically, essential...
In the last decade, a new area of research, referred to as femtomagnetism, has developed within field magnetism, which studies excitation and control magnetic medium dynamics on time scales comparable or even much shorter than those spin-lattice, spin-orbit, exchange interactions. Among many femtomagnetic processes studied date, opto-magnetic interaction femtosecond laser pulses with media is particular interest. This based nondissipative Raman-type mechanisms enables coherent spin be...
The ability to switch ferroics (ferro-, ferri-, antiferromagnets, ferroelectrics, multiferroics) between two stable bit states is one of the keystones modern data storage technology. Due many new ideas, originating from fundamental research during last 50 years, this technology has developed in a breath-taking fashion. Finding conceptually way control ferroic state medium with lowest possible production heat and at fastest timescale challenge condensed matter research. Controlling media by...
Coherent THz optical lattice and hybridized phonon-magnon modes are triggered by femtosecond laser pulses in the antiferromagnetic van der Waals semiconductor FePS
Controlled generation of coherent spin waves with highest possible frequencies and shortest wavelengths is a cornerstone spintronics magnonics. Here, using Heisenberg antiferromagnet RbMnF3, we demonstrate that laser-induced THz dynamics corresponding to pairs mutually counter-propagating the wavevectors up edge Brillouin zone cannot be understood in terms magnetization antiferromagnetic (Néel) vectors, conventionally used describe waves. Instead, propose model such correlation function. We...
We demonstrate experimentally that excitation of a Co-substituted ferrimagnetic yttrium iron garnet thin film with linearly polarized 100 fs laser pulses triggers large-angle magnetization precession an amplitude, phase, and frequency determined by the characteristics pulse. The results from light-induced anisotropy field characteristic lifetime 20 ps, direction which is polarization light. Its strength for pump intensity $25\text{ }\text{mJ}/{\text{cm}}^{2}$ 250 G comparable to intrinsic...
We present a femtosecond spectroscopic magneto-optical investigation of the coherent and incoherent spin dynamics in antiferromagnetic dielectric ${\text{KNiF}}_{3}$. The pathways photoinduced energy flow to spins were controlled by tuning pump photon energy. In particular, we demonstrate that laser pulses, with tuned nearly-zero-absorption region, excite system without any signatures heating electrons or phonons. this regime ultrafast excitation waves is followed gradual increase...
The development of spintronic emitters broadband terahertz (THz) pulses relies on designing heterostructures in which the processes laser-driven spin current generation and subsequent spin-to-charge conversion are most efficient. interface between ferromagnetic nonmagnetic layers an emitter is a critical element. In this study, we experimentally examined single-cycle THz pulse from laser-pulse-excited Pt/Co with 1.2-nm-thick composition-gradient Pt Co compared it emission conventional...
<title>Abstract</title> Radiation from an uniformly moving source, referred to as the Cherenkov effect, is a universal phenomenon, which enables emission of waves and finds important applications in various areas physics particle plasmonics beyond. Currently, unveiling potential coherent spin waves, or magnons, hampered by lack experimentally implemented fast-moving magnetic perturbations. In this work, we uncover magnon-Cherenkov effect demonstrating exchange enabled optically induced...
We report on optical studies of the thin films multiferroic hexagonal (P.G. 6mm) rare-earth orthoferrites RFeO3 (R = Ho, Er, Lu) grown epitaxially a (111)-surface ZrO2(Y2O3) substrate. The absorption study in range 0.6–5.6 eV shows that are transparent below 1.9 eV; above this energy four broad intense bands distinguished. spectra analyzed taking into account unusual fivefold coordination Fe3+ ion. Temperature dependence at 4.9 anomaly 124 K, which we attribute to magnetic ordering iron sublattices.
Ultrafast optical excitation of a metal ferromagnetic film results in modification the magnetocrystalline anisotropy and induces magnetization precession. We consider two main contributions to these processes: an effect noncoherent phonons, which modifies temperature dependent parameters coherent phonons form strain contributing via inverse magnetostriction. Contrary earlier experiments with high-symmetry structures, where mechanisms could not be separated, we study response femtosecond...
We explore a thermal mechanism of changing the magnetic anisotropy by using femtosecond laser pulses in low-symmetry dielectric ferrimagnetic garnet ${(\mathrm{YBiPrLu})}_{3}{(\mathrm{FeGa})}_{5}{\mathrm{O}}_{12}$ film grown on (210)-type ${\mathrm{Gd}}_{3}{\mathrm{Ga}}_{5}{\mathrm{O}}_{12}$ substrate as model media. Employing spectral magneto-optical pump-probe technique and phenomenological analysis, we demonstrate that magnetization precession this is result laser-induced changes...
Abstract Picosecond strain pulses are a versatile tool for investigation of mechanical properties meso- and nano-scale objects with high temporal spatial resolutions. Generation such is traditionally realized via ultrafast laser excitation light-to-strain transducer involving thermoelastic, deformation potential, or inverse piezoelectric effects. These approaches unavoidably lead to heat dissipation temperature rise, which can modify delicate specimens, like biological tissues, ultimately...
We present and analyze high-resolution $\ensuremath{\alpha}$-, $\ensuremath{\sigma}$-, $\ensuremath{\pi}$-polarized absorption spectra related to d-d electronic transitions in tetragonal metaborate CuB${}_{2}$O${}_{4}$ where copper Cu${}^{2+}$ ions occupy two crystallographically distinct 4$b$ 8$d$ positions. The are characterized by exceptionally rich fine structure the spectral range of 1.4--2.4 eV. Six zero-phonon (ZP) lines originating from within both positions distinguished identified....
Laser-induced ultrafast demagnetization in ferrimagnetic Gd${}_{x}$Fe${}_{100\ensuremath{-}x\ensuremath{-}y}$Co${}_{y}$ thin films was studied experimentally as a function of Gd concentration ($x=18$, 22, 24, 30%, and $y\ensuremath{\approx}9$--10%), pump fluence, sample temperature. The results showed that the conditions for full at time scale metal are easily achieved below magnetization compensation point (${T}_{M}$) and, furthermore, when ratio between Fe concentrations is not too large....
Abstract Demands for miniaturization, increasing the operation speed and energy efficiency of electronic devices led to emergence rapid development spin electronics, or spintronics. Several areas experimental theoretical research are considered, in which Ioffe Institute is actively involved. We discuss current progress developing semiconductor hybrid structures that exhibit specified magnetic properties, methods manipulating individual spins, a description switching metallic heterostructures...