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arXiv · 1703.01155

Improper multiferroicity and colossal dielectric constants in Bi$_{2}$CuO$_{4}$

Jitender Kumar·Soumendra Nath Panja·Amit Kumar Naiya·Sunil Nair
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Abstract

The layered cuprate Bi$_{2}$CuO$_{4}$ is investigated using magnetic, dielectric and pyroelectric measurements. This system is observed to be an improper multiferroic, with a robust ferroelectric state being established near the magnetic transition. Magnetic and dielectric measurements indicate the presence of a region above the antiferromagnetic Neel temperature with concomitant polar and magnetic short range order. Bi$_{2}$CuO$_{4}$ is also seen to exhibit colossal dielectric constants at higher temperatures with clearly distinguishable grain and grain boundary contributions, both of which exhibit non-Debye relaxation.

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Jitender Kumar, Soumendra Nath Panja, Amit Kumar Naiya, Sunil Nair. 2017-03-03. Improper multiferroicity and colossal dielectric constants in Bi$_{2}$CuO$_{4}$. https://arxiv.org/abs/1703.01155

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