TY  - JOUR
A1  - He, Jiangang
A1  - Di Sante, Domenico
A1  - Li, Ronghan
A1  - Chen, Xing-Qiu
A1  - Rondinelli, James M.
A1  - Franchini, Cesare
T1  - Tunable metal-insulator transition, Rashba effect and Weyl Fermions in a relativistic charge-ordered ferroelectric oxide
T2  - Nature Communications
N2  - 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 Ag2BiO3 at room temperature. Remarkably, a centrosymmetric BiO6 octahedral-breathing distortion induces a sizable spontaneous ferroelectric polarization through Bi3+/Bi5+ charge disproportionation, which stabilizes simultaneously the insulating phase. The continuous attenuation of the Bi3+/Bi5+ 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 Ag2BiO3 is a promising material for spin-orbitonic applications.
KW  - electronic properties and materials
KW  - ferroelectrics and multiferroics
KW  - topological matter
Y1  - 2018
UR  - https://opus.bibliothek.uni-wuerzburg.de/frontdoor/index/index/docId/22794
UR  - https://nbn-resolving.org/urn:nbn:de:bvb:20-opus-227946
VL  - 9
ER  -