MagDirac · Magnetic Doping of 3D Dirac Semimetals
Horizon 2020 — Marie Skłodowska-Curie Actions
- Duration
- 2019-01-07 → 2021-01-06
- EU contribution
- €172,800
- Participants
- 1
- Scheme
- MSCA-IF
Lines connect the coordinator with its partners.
Results in brief
Magnetic Doping of 3D Dirac Semimetals
After the discovery of 2D Dirac semimetals, the search for the 3D Dirac semimetal with a simple electronic structure continues. In topological Dirac semimetals, the bulk conduction and valence bands touch only at discrete (Dirac) points and disperse linearly along all three momentum directions, forming bulk (3D) Dirac fermions—a natural 3D counterpart of graphene. In addition to these bulk Dirac cones, some Dirac semimetals also possess topological non-trivial surface states, similar to those found in topological insulators. This unique electronic structure of topological Dirac semimetals gives rise to many unusual properties, such as the giant diamagnetism, giant linear magnetoresistance, oscillating quantum spin Hall effect and ultrahigh carrier mobility. In addition, an external magnetic field or magnetic doping in these materials can implement the breaking of the time-reversal symmetry, resulting Weyl semimetal phase. Therefore, here we proposed to investigate how the topological state (Dirac or Weyl) of semimetals can be tuned via its magnetic state. The overall objective of the project is to understand the interplay between magnetism and topological state of Dirac semimetals. This involves the growth of high quality single-crystalline thin films of 3D Dirac semimetals and controlling their magnetic state via magnetic doping.
Data: CORDIS, © European Union
Project objective
A new field in condensed matter physics has emerged, dealing with new quantum states of matter originating from non-trivial topologies of the electronic band structure. Topological insulators were the first class of such materials. Dirac and Weyl semimetals are becoming the focus of the next major waive of research on topological matter. In these materials, the bulk valence band and conduction band touch at discrete points and disperse linearly (3D analogues of graphene). This project aims to answer a key fundamental question in this field: can time-reversal symmetry (TRS) breaking induce a Weyl state in a Dirac semimetal? The originality of our project resides on the idea of switching between Dirac and Weyl states using magnetism (TRS breaking), as the ON-OFF switch, instead of inferring the role of TRS by investigating Dirac and Weyl states in different compounds. We will synthesize epitaxial thin films of Cd3As2, the model 3D TDS, and induce a ferromagnetic state via magnetic doping. Subsequently we will perform a thorough investigation of the band structure (Dirac/Weyl cones, surface states and Fermi arcs), aiming to understand the coupling between magnetic and topological states, in particular, the switching between Dirac and Weyl states by breaking and restoring of TRS. In addition to its fundamental interest, this work has the potential to open a new research field dedicated to electrical switching between topological states, to be exploited in Dirac/Weyl-based electronic devices.
Original text from CORDIS.
Participants
- KATHOLIEKE UNIVERSITEIT LEUVEN · LeuvenCoordinatorBelgium
Links
Data: CORDIS, © European Union