Univ. Paris-Saclay

Service de Physique de l'Etat Condensé

GHz and sub-THz magnonics using ferro- and anti-ferromagnetic insulators
Romain Lebrun
Unité Mixte de Physique CNRS/Thales, Université Paris Saclay, Palaiseau
Mercredi 26/04/2023, 11:15-12:00
CEA Bât 774, Amphi Claude Bloch, Orme des Merisiers

Spin waves are collective spin excitations in a magnetically ordered material. In the classical regime, an intense field of research, named magnonics, targets spin-wave based computing relying on their integration as primary information carriers in logic and radiofrequency devices [1]. Beyond this aspect, spin-wave quanta, i.e., the magnons, can also bring promising perspectives for emerging quantum technologies [2]. In this talk, I will first present some of our recent efforts towards the development of on chip GHz analog devices using spin-waves (such as a spin-wave microwave delay or an amplifier [3]), and towards the observation and the control of magnon Bose-Einstein condensate.
Secondly, I will discuss how magnonics could benefit from the integration of antiferromagnetic materials that brings the prospect of devices operating at THz frequencies. Recent works highlighted how uncoherent magnons can propagate spin-information over long-distances insulating antiferromagnets [4,5]. However, efficiently excitation and detecting coherent magnons remains key challenging tasks to develop antiferromagnetic magnonic. Here I will show that one can use DC spin-current to detect antiferromagnetic resonance [6] and propagating spin-waves in a canted antiferromagnet [7]. Finally, I will highlight the possibility to achieve optically induced narrow band THz emission in antiferromagnetic materials using ultra-fast spin-currents [8]. These results highlight promising perspectives to develop antiferromagnetic phononic and opto-magnonic devices.


[1] A. V. Chumak et al., Advances in Magnetics Roadmap on Spin-Wave Computing, IEEE Trans. Magn. 58, 1 (2022).

[2] L. Trifunovic, F. L. Pedrocchi, and D. Loss, Long-Distance Entanglement of Spin Qubits via Ferromagnet, Phys. Rev. X 3, 041023 (2013).

[3] H. Merbouche, B. Divinskiy, D. Gouéré, R. Lebrun, A. El-Kanj, V. Cros, P. Bortolotti, A. Anane, S. O. Demokritov, and V. E. Demidov, True
Amplification of Spin Waves in Magnonic Nano-Waveguides, arXiv:2303.04695.

[4] R. Lebrun, A. Ross, S. A. Bender, A. Qaiumzadeh, L. Baldrati, J. Cramer, A. Brataas, R. A. Duine, and M. Kläui, Tunable Long-Distance
Spin Transport in a Crystalline Antiferromagnetic Iron Oxide, Nature 561, 222 (2018).

[5] R. Lebrun, A. Ross, O. Gomonay, V. Baltz, U. Ebels, A.-L. Barra, A. Qaiumzadeh, A. Brataas, J. Sinova, and M. Kläui, Long-Distance Spin-
Transport across the Morin Phase Transition up to Room Temperature in Ultra-Low Damping Single Crystals of the Antiferromagnet α-Fe 2
O 3, Nat. Commun. 11, 1 (2020).

[6] I. Boventer, H. T. Simensen, A. Anane, M. Kläui, A. Brataas, and R. Lebrun, Room-Temperature Antiferromagnetic Resonance and
Inverse Spin-Hall Voltage in Canted Antiferromagnets, Phys. Rev. Lett. 126, 187201 (2021).

[7] A. E. Kanj, O. Gomonay, I. Boventer, P. Bortolotti, V. Cros, A. Anane, and R. Lebrun, Evidence of Non-Degenerated, Non-Reciprocal and
Ultra-Fast Spin-Waves in the Canted Antiferromagnet {alpha}-Fe2O3, arXiv:2301.06329.

[8] E. Rongione et al., Emission of Coherent THz Magnons in an Antiferromagnetic Insulator Triggered by Ultrafast SpinPhonon
Interactions, Nat. Commun. 14, 1 (2023).

Coffee and pastries will be served in the hall at 11 am

Contact : Marceau HENOT


Retour en haut