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arXiv · 0908.0773

Giant Magneto-electric Effect in the Novel Mott Insulator, Sr2IrO4

S. Chikara·O. Korneta·W. P. Crummett·L. E. DeLong·P. Schlottmann·G. Cao
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Abstract

Our magnetic, electrical, and thermal measurements on single-crystals of the novel Mott insulator, Sr2IrO4, reveal a novel giant magneto-electric effect (GME) arising from a frustrated magnetic/ferroelectric state whose signatures are: (1) a strongly enhanced electric permittivity that peaks near a newly observed magnetic anomaly at 100 K, (2) a large (~100%) magneto-dielectric shift that occurs near a metamagnetic transition, and (3) magnetic and electric polarization hysteresis. The GME and electric polarization hinge on a spin-orbit gapping of 5d-bands, rather than the magnitude and spatial dependence of magnetization, as traditionally accepted.

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S. Chikara, O. Korneta, W. P. Crummett, L. E. DeLong, P. Schlottmann, G. Cao. 2009-08-05. Giant Magneto-electric Effect in the Novel Mott Insulator, Sr2IrO4. https://doi.org/10.1063/1.3362912

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