We have performed a literature study, prepared and published a manuscript on the physics of optical control and detection of the antiferromagnetic Néel vector in altermagnets and beyond (A. V. Kimel, B. I. Ivanov, Th. Rasing, JMMM 598, 172039 (2024)).
We show that the regime of ultrafast toggle switching can be also realized via a mechanism without relying on heat. This new regime of ‘cold’ toggle switching can be observed in ferrimagnets without a compensation point and over an exceptionally broad temperature range. The control of magnetic anisotropy required for the toggle switching exhibits reduced dissipation compared to laser-induced-heating mechanism, however the dissipation and the switching-time are shown to be competing parameters (T. Zalewski et al, Nature Communications 15, 4451 (2024)).
We have studied the effect of metasurfaces on the efficiency of excitation of spin resonances in antiferromagnetic YFeO3 and yttrium iron garnet Y3Fe5O12. In particular, using the magneto-optical Faraday effect as a probe, we experimentally demonstrate that due to the metasurface the electromagnetic field, otherwise described by plane waves, acquires an out-of-plane magnetic field component and resonantly enhances the field at the frequency of the Gd-Fe spin resonance in the ferrimagnet.
We showed that a coherent magnonic state can substantially change the properties of an antiferromagnet, enabling a new nonlinear path of controlling spins by a pair of THz pulses. The effect is analogous to electronic or ionic Raman scattering, but involves exclusively magnonic excitations and can be thus called magnonic Raman scattering or THz-mediated magnon-magnon coupling. Our work shows that although the efficient control of antiferromagnetism in thermodynamic equilibrium is still a challenge, the problem can be solved by pushing antiferromagnets into a nonequilibrium state where the susceptibility of spins to an external magnetic field is boosted (T. G. H. Blank et al, Phys. Rev. Lett. 131, 096701(2023)).
We showed that a single-cycle terahertz electric field triggers in the topological antiferromagnet MnBi2Te4 strongly anharmonic lattice dynamics, which initiates a light-mediated interaction between otherwise noninteracting phonons. (T. G. H. Blank et al, Phys. Rev. Lett. 131, 026902 (2023)).
We reported on a new regime of magnon-phonon dynamics, which in the vicinity of the Fermi resonance condition, facilitates a mutual, anharmonic energy exchange between magnons and phonons. (T, W. J. Metzger et al, Nature Communications 15, 5472 (2024)).
We showed that the spontaneous magnetization gained temporarily by means of the ultrafast Barnett effect, through the resonant excitation of circularly polarized optical phonons in a paramagnetic substrate, can be used to permanently reverse the magnetic state of a heterostructure mounted atop the said substrate. With the handedness of the phonons steering the direction of magnetic switching, the ultrafast Barnett effect offers a selective and potentially universal method for exercising ultrafast non-local control over magnetic order (C. S. Davies et al, Nature 628, 540–544 (2024)).
