We found a match
Your institution may have access to this item. Find your institution then sign in to continue.
- Title
Multiferroic Behavior in Elemental Selenium below 40 K: Effect of Electronic Topology.
- Authors
Pal, Anirban; Shirodkar, Sharmila N.; Gohil, Smita; Ghosh, Shankar; Waghmare, Umesh V.; Ayyub, Pushan
- Abstract
The quasi-one-dimensional, chiral crystal structure of Selenium has fascinating implications: we report simultaneous magnetic and ferroelectric order in single crystalline Se microtubes below ≈40 K. This is accompanied by a structural transition involving a partial fragmentation of the infinite chains without losing overall crystalline order. Raman spectral data indicate a coupling of magnons with phonons and electric field, while the dielectric constant shows a strong dependence on magnetic field. Our first-principles theoretical analysis reveals that this unexpected multiferroic behavior originates from Selenium being a weak topological insulator. It thus exhibits stable electronic states at its surface, and magnetism emerges from their spin polarization. Consequently, the broken two-fold rotational symmetry permits switchable polarization along its helical axis. We explain the observed magnetoelectric couplings using a Landau theory based on the coupling of phonons with spin and electric field. Our work opens up a new class of topological surface-multiferroics with chiral bulk structure.
- Subjects
MULTIFERROIC materials; FERROELECTRIC crystals; SELENIUM; ELECTRIC fields; MAGNONS
- Publication
Scientific Reports, 2013, p1
- ISSN
2045-2322
- Publication type
Article
- DOI
10.1038/srep02051