2008/09/11 by R. V. K. Mangalam, Nirat Ray, Umesh V. Waghmare +2 · 2 citations
Materials Science · Physics and Astronomy · #Ferroelectric and Piezoelectric Materials #Magnetic and transport properties of perovskites and related materials #Multiferroics and related materials #cond-mat.mtrl-sci #cond-mat.str-el
paper · pdf · doi:10.1016/j.ssc.2008.10.023
15 pages, 5 figures
arxiv created 2008/09/11 · openalex publication_date 2008/10/29 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/29
Some of the Multiferroics [1] form a rare class of materials that exhibit magnetoelectric coupling arising from the coexistence of ferromagnetism and ferroelectricity, with potential for many technological applications.[2,3] Over the last decade, an active research on multiferroics has resulted in the identification of a few routes that lead to multiferroicity in bulk materials.[4-6] While ferroelectricity in a classic ferroelectric such as BaTiO3 is expected to diminish with the reducing particle size,[7,8] ferromagnetism cannot occur in its bulk form.[9] Here, we use a combination of experiment and first-principles simulations to demonstrate that multiferroic nature emerges in intermediate size nanocrystalline BaTiO3, ferromagnetism arising from the oxygen vacancies at the surface and ferroelectricity from the core. A strong coupling between a surface polar phonon and spin is shown to result in a magnetocapacitance effect observed at room temperature, which can open up possibilities of new electro-magneto-mechanical devices at the nano-scale.