Ultrafast Coherent THz Lattice Dynamics Coupled to Spins in the van der Waals Antiferromagnet FePS.

Coherent THz optical lattice and hybridized phonon-magnon modes are triggered by femtosecond laser pulses in the antiferromagnetic van der Waals semiconductor FePS . The laser-driven lattice and spin dynamics are investigated in a bulk crystal as well as in a 380 nm-thick exfoliated flake as a function of the excitation photon energy, sample temperature and applied magnetic field. The pump-probe magneto-optical measurements reveal that the amplitude of a coherent phonon mode oscillating at 3.

Spatially selective excitation of spin dynamics in magneto-photonic crystals by spectrally tunable ultrashort laser pulses.

In this work, we tackle the problem of the spatially selective optical excitation of spin dynamics in structures with multiple magnetic layers. The 120 fs circularly polarized laser pulses were used to launch magnetization precession in an all-dielectric magneto-photonic crystals (MPC) formed by magnetic layers sandwiched between and inside two magnetic Bragg mirrors. Optical pump-probe experiments reveal magnetization precession triggered via ultrafast inverse Faraday effect with an amplitude strongly dependent on the pump central wavelength: maxima of the amplitude are achieved for the wavelength tuned at the cavity resonance and at the edge of the photonic bandgap.

Spin reorientation transition in CoFeB/MgO/CoFeB tunnel junction enabled by ultrafast laser-induced suppression of perpendicular magnetic anisotropy.

Magnetic tunnel junction (MTJ) is a leading contender for next generation high-density nonvolatile memory technology. Fast and efficient switching of MTJs between different resistance states is a challenging problem, which can be tackled by using an unconventional stimulus-a femtosecond laser pulse. Herein, we report an experimental study of the laser-induced magnetization dynamics in a CoFeB/MgO/CoFeB (CoFeB/MgO/CoFeB) MTJ with ultrathin CoFeB electrodes possessing perpendicular magnetic anisotropy (PMA).

Large non-thermal contribution to picosecond strain pulse generation using the photo-induced phase transition in VO.

Picosecond strain pulses are a versatile tool for investigation of mechanical properties of meso- and nano-scale objects with high temporal and spatial resolutions. Generation of such pulses is traditionally realized via ultrafast laser excitation of a light-to-strain transducer involving thermoelastic, deformation potential, or inverse piezoelectric effects. These approaches unavoidably lead to heat dissipation and a temperature rise, which can modify delicate specimens, like biological tissues, and ultimately destroy the transducer itself limiting the amplitude of generated picosecond strain.

Dissecting spin-phonon equilibration in ferrimagnetic insulators by ultrafast lattice excitation.

To gain control over magnetic order on ultrafast time scales, a fundamental understanding of the way electron spins interact with the surrounding crystal lattice is required. However, measurement and analysis even of basic collective processes such as spin-phonon equilibration have remained challenging. Here, we directly probe the flow of energy and angular momentum in the model insulating ferrimagnet yttrium iron garnet.