Low-temperature ferroelectric phase and magnetoelectric coupling in underdoped La2CuO4+x
Abstract
We report the discovery of ferroelectricity below 4.5 K in highly underdoped La2CuO4+x accompanied by slow charge dynamics which develop below T ∼ 40 K. An anisotropic magnetoelectric response has also been observed, indicating considerable spin-charge coupling in this lightly doped parent high-temperature copper-oxide superconductor. The ferroelectric state is proposed to develop from polar nanoregions, in which spatial inversion symmetry is locally broken due to nonstoichiometric carrier doping.
- Publication:
-
Physical Review B
- Pub Date:
- June 2012
- DOI:
- 10.1103/PhysRevB.85.214502
- arXiv:
- arXiv:1111.0050
- Bibcode:
- 2012PhRvB..85u4502V
- Keywords:
-
- 74.72.Gh;
- 74.81.-g;
- 75.85.+t;
- 77.80.Jk;
- Inhomogeneous superconductors and superconducting systems;
- Condensed Matter - Superconductivity;
- Condensed Matter - Materials Science;
- Condensed Matter - Strongly Correlated Electrons
- E-Print:
- 7 Pages, 6 Figures, supplementary material