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arXiv · 1009.4792

Tuning of dielectric properties and magnetism of SrTiO3 by site-specific doping of Mn

D. Choudhury·S. Mukherjee·P. Mandal·A. Sundaresan·U. V. Waghmare·S. Bhattacharjee·R. Mathieu·P. Lazor·O. Eriksson·B. Sanyal·P. Nordblad·A. Sharma·S. V. Bhat·O. Karis·D. D. Sarma
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Abstract

Combining experiments with first principles calculations, we show that site-specific doping of Mn into SrTiO3 has a decisive influence on the dielectric properties of these doped systems. We find that phonon contributions to the dielectric constant invariably decrease sharply on doping at any site. However, a sizable, random dipolar contribution only for Mn at the Sr site arises from a strong off-centric displacement of Mn in spite of Mn being in a non-d0 state; this leads to a large dielectric constant at higher temperatures and gives rise to a relaxor ferroelectric behavior at lower temperatures. We also investigate magnetic properties in detail and critically reevaluate the possibility of a true multi-glass state in such systems.

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D. Choudhury, S. Mukherjee, P. Mandal, A. Sundaresan, U. V. Waghmare, S. Bhattacharjee, R. Mathieu, P. Lazor, O. Eriksson, B. Sanyal, P. Nordblad, A. Sharma, S. V. Bhat, O. Karis, D. D. Sarma. 2010-09-24. Tuning of dielectric properties and magnetism of SrTiO3 by site-specific doping of Mn. https://doi.org/10.1103/physrevb.84.125124

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