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arXiv · 1111.0050

Low-temperature ferroelectric phase and magnetoelectric coupling in the underdoped La_2CuO_(4+x)

Z. Viskadourakis·I. Radulov·A. P. Petrović·S. Mukherjee·B. M. Andersen·G. Jelbert·N. S. Headings·S. M. Hayden·K. Kiefer·S. Landsgesell·D. N. Argyriou·C. Panagopoulos
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Abstract

We report the discovery of a ferroelectric ground state below 4.5 K in highly underdoped La_2CuO_(4+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 non-stoichiometric carrier doping.

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Z. Viskadourakis, I. Radulov, A. P. Petrović, S. Mukherjee, B. M. Andersen, G. Jelbert, N. S. Headings, S. M. Hayden, K. Kiefer, S. Landsgesell, D. N. Argyriou, C. Panagopoulos. 2011-10-31. Low-temperature ferroelectric phase and magnetoelectric coupling in the underdoped La_2CuO_(4+x). https://doi.org/10.1103/physrevb.85.214502

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