Observation of Coherent Helimagnons and Gilbert damping in an Itinerant Magnet

Abstract

We study the magnetic excitations of itinerant helimagnets by applying time-resolved optical spectroscopy to Fe0.8Co0.2Si. Optically excited oscillations of the magnetization in the helical state are found to disperse to lower frequency as the applied magnetic field is increased; the fingerprint of collective modes unique to helimagnets, known as helimagnons. The use of time-resolved spectroscopy allows us to address the fundamental magnetic relaxation processes by directly measuring the Gilbert damping, revealing the versatility of spin dynamics in chiral magnets. (*These authors contributed equally to this work)

References in corpus (2)

• Rotating skyrmion lattices by spin torques and field or temperature gradients
• Detection of coherent magnons via ultrafast pump-probe reflectance spectroscopy in multiferroic Ba0.6Sr1.4Zn2Fe12O22

Cited by in corpus (4)

• Microwave spectroscopy of the low-temperature skyrmion state in Cu2OSeO3
• Optically excited spin dynamics of thermally metastable skyrmions in Fe${}_{0.75}$Co${}_{0.25}$Si
• Optical creation and annihilation of skyrmion patches in a bulk chiral magnet
• Disentangling Electronic, Lattice and Spin Dynamics in the Chiral Helimagnet Cr1/3NbS2