Direct excitation of propagating spin waves by focused ultrashort optical pulses
Keatley, Paul Steven
Van Waeyenberge, B.
Physical Review Letters
American Physical Society
An all-optical experiment long utilized to image phonons excited by ultrashort optical pulses has been applied to a magnetic sample. In addition to circular ripples due to surface acoustic waves, we observe an X-shaped pattern formed by propagating spin waves. The emission of spin waves from the optical pulse epicenter in the form of collimated beams is qualitatively reproduced by micromagnetic simulations. We explain the observed pattern in terms of the group velocity distribution of Damon-Eshbach magnetostatic spin waves in the reciprocal space and the wave vector spectrum of the focused ultrafast laser pulse.
Copyright © 2013 American Physical Society
Vol. 110 (9), article 097201
Place of publication