EuCd2As2: A Magnetic Semiconductor
EuCd2As2 is now widely accepted as a topological semimetal in which a Weyl phase is induced by an external magnetic field. We challenge this view through firm experimental evidence using a combination of electronic transport, optical spectroscopy, and excited-state photoemission spectroscopy. We show that the EuCd2As2 is in fact a semiconductor with a gap of 0.77 eV. We show that the externally applied magnetic field has a profound impact on the electronic band structure of this system. This is manifested by a huge decrease of the observed band gap, as large as 125 meV at 2 T, and, consequently, by a giant redshift of the interband absorption edge. However, the semiconductor nature of the material remains preserved. EuCd2As2 is therefore a magnetic semiconductor rather than a Dirac or Weyl semimetal, as suggested by ab initio computations carried out within the local spin-density approximation.
WOS:001101160800004
2023-11-03
131
18
186704
REVIEWED
Funder | Grant Number |
Swiss National Science Foundation | PP00P2_202661 |
NCCR MARVEL | |
SNSF | 200021_200362 |
CeNIKS project | |
Croatian Government | |
EU through the European Regional Development Fund Competitiveness and Cohesion Operational Program | KK.01.1.1.02.0013 |
ANR DIRAC3D | |
LNCMI-CNRS | |
Foundation for Polish Science through the International Research Agendas program | |
European Union within the Smart Growth Operational Programme | |
European Research Council (ERC Consolidator Grant) | 725521 |