Unusual spin-orbit couplings in antiferromagnets. – (Revaz Ramazashvili / LPT / HDR). – 11/02/2025, 14H

Soutenance de HDR

Revaz Ramazashvili, LPT, Salle de conférence, Bat. 3R4

Summary:

This work is devoted to unusual spin-orbit couplings in antiferromagnets: those that fall outside the textbook classification by order of the expansion in the inverse speed of light 1/c. Contrary to the textbook Pauli spin-orbit coupling that arises only at second order in 1/c, the unusual couplings of this work appear already at first and zeroth order in 1/c:

– The Zeeman spin-orbit coupling, arising from a substantial momentum dependence of the g-tensor, is first-order in 1/c.

– A smooth texture (non-uniform configuration) of the Néel order parameter generates a spin-orbit coupling that is of order zero in 1/c.

Both the Zeeman and the texture-induced spin-orbit coupling produce anomalous effects that are also a subject of this work.