Speaker: Shu(Suzy) Zhang(Max Planck Institute, Dresden)

Host: Rebecca Flint

Title: A Dynamical Landscape of Quantum Magnetism

Abstract:

The emergence of novel magnetism stands as a hallmark of quantum materials, which has unveiled fascinating complexity arising from the interplay between quantum mechanics and many-body interactions. In this talk, we delve into the study of collective spin dynamics in quantum materials, which provides critical insights into exotic magnetic phases of matter and their dynamical and transport behaviors, as well as fosters innovative approaches in the realm of quantum information. We will explore a hydrodynamic picture of the spin dynamics in a three-dimensional quantum spin liquid candidate material, where strong quantum fluctuations defy a conventional magnetic order [1]. Our complementary analytical and numerical theories reveal an interactive coexistence of fast spin waves and slow ground-state motions, which produces an excitation spectrum that quantitatively agrees with inelastic neutron scattering experimental data [2,3]. This hydrodynamic understanding holds a general implication for spin dynamics and transport in the presence of frustrated magnetic interactions, where spin diffusion can manifest in an intermediate temperature regime as an intrinsic many-body effect [4]. In the final part, we offer a glimpse into the transformative potential of magnetic materials in the quantum-information domain. We envision a hybrid system, where the long-range spin correlations inherent in a magnetically active platform can generate stable entanglement between spin qubits [5].

[1]. K. W. Plumb, H. J. Changlani, A. Scheie, SZ, …, R. J. Cava, C. L. Broholm, Nat. Phys. 15, 54 (2019)

[2]. SZ, H. J. Changlani, K. W. Plumb, O. Tchernyshyov, and R. Moessner, Phys. Rev. Lett. 122, 167203 (2019)

[3]. A. Bhardwaj, SZ, H. Yan, R. Moessner, A. H. Nevidomskyy, H. J. Changlani, npj Quantum Mater. 7, 51 (2022)

[4]. N. Mao, D. Dahlbom, R. Moessner, Y Zhang, SZ, in preparation (2024)

[5]. J. Zou, SZ, Y. Tserkovnyak,  Phy. Rev. B 106, L180406 (2022)

Biography:

I obtained my Bachelor degree in 2014 from Tsinghua University in Beijing, China, and my Ph.D. in 2019 from the Johns Hopkins University. In 2019, I was a Graduate Fellow at the Kavli Institute for Theoretical Physics at the University of California, Santa Barbara. From 2019-2021, I worked as a postdoctoral scholar in  University of California, Los Angeles, and received the Chancellor’s Award for Postdoctoral Research. Currently, I hold a position of Distinguished PKS Postdoctoral Fellow at Max Planck Institute for the Physics of Complex Systems in Dresden, Germany.