Dr. Wencan Jin, Auburn University
Hybrid magnon-phonon cavity realized in a magnetoelastic heterostructure
Abstract – Strong coupling between two quantized excitations leads to a hybridized state that allows to explore new phenomena and technologies. Phononic excitations, such as long-lived, high-overtone acoustic waves, can host many well-isolated modes at the same frequency. Meanwhile, magnetic excitations or magnons in magnetically-ordered materials show frequency tunability and can strongly couple with phonons. In this study, using the combination of analytical model, epitaxial growth, and spectroscopy characterization, we design a hybrid magnon-phonon cavity based on the La0.7Sr0.3MnO3/SrTiO3 (LSMO/STO) heterostructure with magnetoelastic coupling at the interface. Ferromagnetic resonance (FMR) measurements demonstrate strong coupling between the Kittel magnon of LSMO and the standing wave of transverse acoustic phonon of STO, as evidenced by their anticrossings in the FMR spectra. Remarkably, when the STO undergoes a cubic-to-tetragonal phase transition at TS~105 K, the Kittel magnon of LSMO splits into three bands due to the anisotropic strains along the [100], [010], and [001] crystalline orientations, forming a network of hybrid magnon-phonon modes that are sensitive to strain engineering. Our work highlights high-quality magnetoelastic heterostructures as a suitable material platform to implement magnon-phonon hybrids, holding the promise of storing, encoding, and transducing coherent information between magnon and phonon modes.
Bio – Wencan Jin graduated from Renmin University of China in 2011. He received his Ph.D. from Columbia University in 2017. He then worked as a Postdoctoral Researcher at the University of Michigan, Ann Arbor and joined Auburn University as an Assistant Professor of Physics and Adjunct Professor of Electrical and Computer Engineering in 2019. His research focuses on optical spectroscopy (Raman, SHG) and photoemission spectroscopy (ARPES, XPS) studies of novel quantum materials with emphasis of ferroic orders in 2D vdW materials and complex oxides.
This is an in-person seminar. If you opt to join via zoom use Meeting ID 824 5649 1345, Passcode 994582