Extreme terahertz magnon multiplication induced by resonant magnetic pulse pairs

C Huang; L Luo; M Mootz; J Shang; P Man; L Su; I E Perakis; Y X Yao; A Wu; J Wang

doi:10.1038/s41467-024-47471-6

Extreme terahertz magnon multiplication induced by resonant magnetic pulse pairs

Nat Commun. 2024 Apr 13;15(1):3214. doi: 10.1038/s41467-024-47471-6.

Authors

C Huang^#^{1

2}, L Luo^#¹, M Mootz¹, J Shang^{3

4}, P Man^{3

4}, L Su^{3

4}, I E Perakis⁵, Y X Yao¹, A Wu^{3

4}, J Wang^{6

7}

Affiliations

¹ Ames National Laboratory, Ames, IA, 50011, USA.
² Department of Physics and Astronomy, Iowa State University, Ames, IA, 50011, USA.
³ State Key Laboratory of High Performance Ceramics and Superfine Microstructure, Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai, 201899, China.
⁴ Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing, 100049, China.
⁵ Department of Physics, University of Alabama at Birmingham, Birmingham, AL, 35294-1170, USA.
⁶ Ames National Laboratory, Ames, IA, 50011, USA. jgwang@iastate.edu.
⁷ Department of Physics and Astronomy, Iowa State University, Ames, IA, 50011, USA. jgwang@iastate.edu.

^# Contributed equally.

Abstract

Nonlinear interactions of spin-waves and their quanta, magnons, have emerged as prominent candidates for interference-based technology, ranging from quantum transduction to antiferromagnetic spintronics. Yet magnon multiplication in the terahertz (THz) spectral region represents a major challenge. Intense, resonant magnetic fields from THz pulse-pairs with controllable phases and amplitudes enable high order THz magnon multiplication, distinct from non-resonant nonlinearities such as the high harmonic generation by below-band gap electric fields. Here, we demonstrate exceptionally high-order THz nonlinear magnonics. It manifests as 7th-order spin-wave-mixing and 6th harmonic magnon generation in an antiferromagnetic orthoferrite. We use THz two-dimensional coherent spectroscopy to achieve high-sensitivity detection of nonlinear magnon interactions up to six-magnon quanta in strongly-driven many-magnon correlated states. The high-order magnon multiplication, supported by classical and quantum spin simulations, elucidates the significance of four-fold magnetic anisotropy and Dzyaloshinskii-Moriya symmetry breaking. Moreover, our results shed light on the potential quantum fluctuation properties inherent in nonlinear magnons.