# Seminar on Condensed Matter Theory

Group of Theoretical Physics at the Department of Condensed Matter Physics

of Charles University has a pleasure to invite you to attend the seminar

on 14th December 2023 at 13:00

at Faculty of Mathematics and Physics of Charles University, Ke Karlovu 5, 121 16 Praha 2

Seminar room **F 052**

### Alberto Marmodoro, Ph.D.

#### Institute of Physics of the Czech Academy of Sciences

## Manifestations of chirality induced spin selectivity (CISS) in terms of generalized transport and x-ray absorption within the inorganic Strukturbericht B20 crystal family: some ab-initio results

# Alberto Marmodoro, Ph.D. » Manifestations of chirality induced spin selectivity (CISS) in terms of generalized transport and x-ray absorption within the inorganic Strukturbericht B20 crystal family: some ab-initio results

*Institute of Physics of the Czech Academy of Sciences*

Location: Seminar room KFKL, MFF UK (room F052 - ground floor near the rear staircase, Ke Karlovu 5)

Magnetism finds a fundamental explanation within relativistic principles applied to the electronic structure of a material. Cases of limited traslational invariance, such as non-centrosymmetric bulk crystals or interfaces across different high-symmetry materials, have long offered fertile grounds for spintronics [1]. In recent years some of these effects have been studied in materials with non-colinear antiferromagnetic order [2]. Yet more recently [3] there has been growing interest for systems where it is the Coulomb rather than the exchange part of the effective atomic potential perceived by electrons which can generate, even by itself, experimental manifestations in terms of generalized transport [4] or spin-polarized ARPES and other types of spectroscopy [5]. In these cases atomic magnetic moment can be zero due to compensation taking place at a smaller length-scale than more commonly studied antiferromagnets [6]. This also means no reliance on magnetic long range order (LRO), i.e. on a high critical temperature, for the above effects to emerge. We have used ab initio relativistic multiple scattering (KKR) / Green's function methods [7] to study examples from the cubic Strukturbericht B20 family, such as AlPt, in terms of spin and orbital magnetic moment \vec k-locked band structure textures, Edelstein response and x-ray absorption dichroism (XCD) [8]. We explore the role of lattice geometry, of spin-orbit coupling and of finite temperature.

[1] G.Dresselhaus, “Spin-Orbit Coupling Effects in Zinc Blende Structures,” Phys. Rev., vol. 100, no. 2, p. 580, 1955.

[2] S.Wimmer et al. “Magneto-optic and transverse-transport properties of noncollinear antiferromagnets,” PRB 100, 214429 (2019).

[3] G.Fecher et al. “Chirality in the Solid State: Chiral Crystal Structures in Chiral and Achiral Space Groups,” Nature Materials 15,17,1 (2022)

[4] K.Shiota et al. “Chirality-Induced Spin Polarization over Macroscopic Distances in Chiral Disilicide Crystals” PRL 127, 126602, (2021)

[5] J.Krieger et al. "Parallel spin-momentum locking in a chiral topological semimetal", Arxiv preprints, https://doi.org/10.48550/arXiv.2210.08221

[6] L.Nordström et al. “Noncollinear intra-atomic magnetism”, PRL 76, 23, 4420 (1996)

[7] H.Ebert et al. “Calculating condensed matter properties using the KKR-Green’s function method—recent developments and applications” Rep.Prog.Phys. 74, 9, 096501 (2011)

[8] C.Natoli et al. “Theory of X-ray natural circular dichroism,” Eur.Phys.J. B 4, 1 (1998)