EuCd2As2 has emerged as a topological material where magnetism may produce strong effects. This compound has been understood as a candidate Weyl semimetal, based mostly on transport and photoemission measurements. I will present our recent results on samples in which we control the carrier concentration through chemical synthesis. We find magneto-optical evidence of a sizeable band gap, remarkably sensitive to the local Eu magnetism. Our results contradict the current consensus on the ground state of this compound, bringing into question its topological nature.
Reference: Santos-Cottin et al., EuCd2As2: a magnetic semiconductor, https://arxiv.org/abs/2301.08014
Location: Stuckelberg, Ecole de Physique
Time: Friday 3 March 2023, 12:00 for pizza, 12:30 start discussion