Nonlinear Responses in Noncentrosymmetric Systems

Date

Aug 7, 2024

Time

11:00 AM - 12:00 PM

Speaker

Dr. Diego Garcia Ovalle

Affiliation

Aix-Marseille Université, CNRS, CINaM, Marseille

Language

en

Main Topic

Materialien

Host

Grit Rötzer

Description

In this presentation I want to illustrate how nonlinear responses can be considered as valuable tools to reveal the electronic properties of quantum materials. Besides, I am going to show that these observables can be identified independently of the material’s topology, opening interesting avenues on the optimization of these effects in topologically trivial systems such as interfaces and heterostructures. My talk will be divided into three sections: First, I am going to demonstrate the role of the surface states on the nonlinear Hall effect driven by the Berry curvature dipole [1], which is the leading order contribution to the second order Hall effect in nonmagnetic materials with inversion symmetry breaking. I will also propose a fundamental discussion on the possibility that a nonlinear Hall response could be quantized and its current state of the art. Second, I will make a detour on spintronics to explain the microscopic origin of the spin-orbit torques allowed by symmetry in trigonal crystals [2], putting the emphasis on one of the terms that is able to promote field-free switching in the perpendicular magnetization via crystal symmetry engineering [3]. Last but not least, I will describe the emergence of an unconventional Hall effect in trigonal crystals [4] that appears when the electric and magnetic field are aligned collinearly, comparing their features to the observation of a similar effect reported in the magnetic Weyl semimetal Co3Sn2S2 [5]. References 1. D.Garcia Ovalle, A.Pezo and A.Manchon. ”Influence of the Surface States on the Nonlinear Hall Effect in Weyl Semimetals”. Phys. Rev. B. 106, 214435 (2022). 2. D.Garcia Ovalle, A.Pezo and A.Manchon. ”Spin-Orbit Torque for Field-Free Switching in C3v Crystals”. Phys. Rev. B. 107, 094422 (2023). 3. L.Liu, C.Zhou, X.Shu et. al. ”Symmetry-Dependent Field-Free Switching of Perpendicular Magnetization”. Nature Nat. 16, 277-282 (2021). 4. L.Liu, Armando Pezo, D.Garcia Ovalle et. al. ”Crystal Symmetry-Dependent In-Plane Hall Effect”. Nano Lett. 24, 2, 733-740 (2024). 5. B. Jiang, L.Wang, R.Bi et. al. ”Chirality-Dependent Hall Effect and Antisymmetric Magnetoresistance in a Magnetic Weyl Semimetal”. Phys. Rev. Lett. 126, 236601 (2021). .

Links

• Seminars at the IFW

Last modified: Aug 7, 2024, 7:38:14 AM