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Title: Efficient Optical Control of Magnon Dynamics in van der Waals Ferromagnets
Optical control of magnons in two-dimensional (2D) materials promises new functionalities for spintronics and magnonics in atomically thin devices. Here, we report control of magnon dynamics, using laser polarization, in a ferromagnetic van der Waals (vdW) material, Fe3.6Co1.4GeTe2. The magnon amplitude, frequency, and lifetime are controlled and monitored by time-resolved pump-probe spectroscopy. We show substantial (over 25%) and continuous modulation of magnon dynamics as a function of incident laser polarization. Our results suggest that the modification of the effective demagnetization field and magnetic anisotropy by the pump laser pulses with different polarizations is due to anisotropic optical absorption. This implies that pump laser pulses modify the local spin environment, which enables the launch of magnons with tunable dynamics. Our first-principles calculations confirm the anisotropic optical absorption of different crystal orientations. Our findings suggest a new route for the development of opto-spintronic or opto-magnonic devices.  more » « less
Award ID(s):
2326944
PAR ID:
10523140
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ; ; ; ; ;
Publisher / Repository:
AAAS
Date Published:
Journal Name:
Ultrafast Science
Edition / Version:
1
Volume:
4
ISSN:
2765-8791
Page Range / eLocation ID:
0064
Subject(s) / Keyword(s):
Ultrafast optics, magnon, 2D materials
Format(s):
Medium: X Size: 7MB Other: pdf
Size(s):
7MB
Sponsoring Org:
National Science Foundation
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