相关论文: Two-photon driven magnon-pair resonance as a signa…
Terahertz (THz) spin waves or their quanta, magnons, can be efficiently excited by acoustic phonons because these excitations have similar wavevectors in the THz regime. THz acoustic phonons can be produced using photoacoustic phenomena but…
We report a new technique for generating magnetic resonance with synchronous modulation of two-photon resonant light fields. Magnetic resonances in fluorescence from a sodium cell are measured to demonstrate suitability of this technique…
Nonlinear processes involving frequency-mixing of light fields set the basis for ultrafast coherent spectroscopy of collective modes in solids. In certain semimetals and semiconductors, generation of coherent phonon modes can occur by a…
We study nonlinear response of a spin $S>1/2$ with easy-axis anisotropy. The response displays sharp dips or peaks when the modulation frequency is adiabatically swept through multiphoton resonance. The effect is a consequence of a special…
The dynamics of a binary neutron stars merger is governed by physics under the most extreme conditions, including strong spacetime curvature, ultra-high matter densities, luminous neutrino emission and the rapid amplification of the initial…
The developing field of strain-induced magnetization dynamics offers a promising path toward efficiently controlling spins and phase transitions. Understanding the underlying mechanisms is crucial in finding the optimal parameters…
The Higgs mode in superconductors is a scalar mode without electric or magnetic dipole moment. Thus, it is commonly believed that its excitation is restricted to a nonlinear two-photon Raman process. However, recent efforts have shown that…
Resonant electron-positron pair production by a high-energy gamma quantum in the field of a nucleus and a quasi-monochromatic laser wave was theoretically studied. Under the resonant condition an intermediate virtual electron (positron) in…
Femtosecond laser light can transfer spin angular momentum between magnetic subspecies that exhibit hybridized valence bands within an alloy or compound, and represents the fastest route for manipulating the magnetization of a material. To…
Optical control of magnetism, of interest for high-speed data processing and storage, has only been demonstrated with near-infrared excitation to date. However, in absorbing materials, such high photon energies can lead to significant…
Nonlinearity of magneto-dynamics is typically described by a single constant, $\mathcal{N}$, with positive and negative values indicating repulsion and attraction of magnons, respectively. In thin magnetic films with easy-plane magnetic…
The resonant process of electron-positron pairproduction by an electron in a subcritical magnetic field has been studied when the pair is produced to exited Landau levels. The spin dependency of the process rate has been analyzed. In the…
We present a systematic investigation of two-photon excitation processes in a GaAs-based microcavity in the strong-coupling regime. We observe second harmonic generation resonant to the upper and lower polariton level, which exhibits a…
Optical generation of complex spin textures is one of the most exciting challenges of modern spintronics. Here, we uncover a distinct physical mechanism for imprinting spin chirality into collinear magnets with short laser pulses. By…
Two-photon lasers require materials with large two-photon gain (2PG) coefficients and low linear and nonlinear losses. Our previous demonstration of large enhancement of two-photon absorption in semiconductors for very different photon…
Ultrafast laser excitation of ferromagnetic metals gives rise to correlated, highly non-equilibrium dynamics of electrons, spins and lattice, which are, however, poorly described by the widely-used three-temperature model (3TM). Here, we…
We demonstrate dynamic control of the lattice by THz light by exploiting the coupling of phonon modes. The low-energy sliding phonon modes in the spin-ladder system, Sr$_{14}$Cu$_{24}$O$_{41}$, are excited using THz radiation with high…
The specific features of nonlinear pair production and radiation processes in an ultratsrong rotating electric field are investigated, taking into account that this field models the antinodes of counterpropagating laser beams. It is shown…
Ultrastrong light-matter coupling opens exciting possibilities to generate squeezed quantum states and entanglement. Here we propose a way to achieve this regime in superconducting hybrid nanostructures with ferromagnetic interlayers.…
We present a mechanism by which optically driven chiral phonon modes in rare-earth trihalides generate giant effective magnetic fields acting on the paramagnetic $4f$ spins. With cerium trichloride (CeCl$_3$) as our example system, we…