Observation of coherent helimagnons and gilbert damping in an itinerant magnet
Publication Type
Journal Article
Authors
Koralek, J.D., D. Meier, J.P. Hinton, A. Bauer, S.A. Parameswaran, A. Vishwanath, Ramamoorthy Ramesh, R.W. Schoenlein, C. Pfleiderer, J. Orenstein
DOI
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 "format"to address the fundamental magnetic relaxation processes by directly measuring the Gilbert damping, revealing the versatility of spin dynamics in chiral magnets. © 2012 American Physical Society.
Journal
Physical Review Letters
Volume
109
Year of Publication
2012
ISSN
00319007