Authors:	Rongione, Enzo Gueckstock, Oliver Mattern, M. Gomonay, Olena Meer, Hendrik Schmitt, Christian Ramos, Rafael Kikkawa, Takashi Mičica, M. Saitoh, E. Sinova, Jairo Jaffrès, Henri Mangeney, J. Goennenwein, Sebastian T. B. Geprägs, Stephan Kampfrath, Tobias Kläui, Mathias Bargheer, M. Seifert, Tom S. Dhillon, Sukhdeep Lebrun, Romain
Title:	Emission of coherent THz magnons in an antiferromagnetic insulator triggered by ultrafast spin–phonon interactions
Online publication date:	19-Jun-2023
Year of first publication:	2023
Language:	english
Abstract:	Antiferromagnetic materials have been proposed as new types of narrowband THz spintronic devices owing to their ultrafast spin dynamics. Manipulating coherently their spin dynamics, however, remains a key challenge that is envisioned to be accomplished by spin-orbit torques or direct optical excita tions. Here, we demonstrate the combined generation of broadband THz (incoherent) magnons and narrowband (coherent) magnons at 1 THz in low damping thin films of NiO/Pt. We evidence, experimentally and through modeling, two excitation processes of spin dynamics in NiO: an off-resonant instantaneous optical spin torque in (111) oriented films and a strain-wave induced THz torque induced by ultrafast Pt excitation in (001) oriented films. Both phenomena lead to the emission of a THz signal through the inverse spin Hall effect in the adjacent heavy metal layer. We unravel the characteristic timescales of the two excitation processes found to be < 50 fs and > 300 fs, respectively, and thus open new routes towards the development of fast opto spintronic devices based on antiferromagnetic materials.
DDC:	530 Physik 530 Physics
Institution:	Johannes Gutenberg-Universität Mainz
Department:	FB 08 Physik, Mathematik u. Informatik
Place:	Mainz
ROR:	https://ror.org/023b0x485
DOI:	http://doi.org/10.25358/openscience-9192
Version:	Published version
Publication type:	Zeitschriftenaufsatz
License:	CC BY
Information on rights of use:	https://creativecommons.org/licenses/by/4.0/
Journal:	Nature Communications 14
Pages or article number:	1818
Publisher:	Nature Publishing Group UK
Publisher place:	London
Issue date:	2023
ISSN:	2041-1723
Publisher DOI:	10.1038/s41467-023-37509-6
Appears in collections:	JGU-Publikationen