Details

Autor(en) / Beteiligte

• He, Jiangang
• Di Sante, Domenico
• Li, Ronghan
• Chen, Xing-Qiu
• Rondinelli, James M
• Franchini, Cesare

Titel

Tunable metal-insulator transition, Rashba effect and Weyl Fermions in a relativistic charge-ordered ferroelectric oxide

Ist Teil von

• Nature communications, 2018-02, Vol.9 (1), p.492-7, Article 492

Ort / Verlag

England: Nature Publishing Group

Erscheinungsjahr

2018

Link zum Volltext

Quelle

Alma/SFX Local Collection

Beschreibungen/Notizen

• Controllable metal-insulator transitions (MIT), Rashba-Dresselhaus (RD) spin splitting, and Weyl semimetals are promising schemes for realizing processing devices. Complex oxides are a desirable materials platform for such devices, as they host delicate and tunable charge, spin, orbital, and lattice degrees of freedoms. Here, using first-principles calculations and symmetry analysis, we identify an electric-field tunable MIT, RD effect, and Weyl semimetal in a known, charge-ordered, and polar relativistic oxide Ag BiO at room temperature. Remarkably, a centrosymmetric BiO octahedral-breathing distortion induces a sizable spontaneous ferroelectric polarization through Bi /Bi charge disproportionation, which stabilizes simultaneously the insulating phase. The continuous attenuation of the Bi /Bi disproportionation obtained by applying an external electric field reduces the band gap and RD spin splitting and drives the phase transition from a ferroelectric RD insulator to a paraelectric Dirac semimetal, through a topological Weyl semimetal intermediate state. These findings suggest that Ag BiO is a promising material for spin-orbitonic applications.