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arXiv · 1907.07882

Charged domain walls and crystallographic microstructures in hybrid improper ferroelectric Ca$_{3-x}$Sr$_x$Ti$_2$O$_7$

Hiroshi Nakajima·Koji Shigematsu·Yoichi Horibe·Shigeo Mori·Yasukazu Murakami
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Abstract

The charged domain walls in ferroelectric materials exhibit intriguing physical properties. We examine herein the charged-domain-wall structures in Ca$_{3-x}$Sr$_x$Ti$_2$O$_7$ using transmission electron microscopy. When viewed along the [001] axis, the wavy charged domain walls are observed over a wide range ($>$5 $\mu$m). In contrast, short charged-domain-wall fragments (from 10 to 200 nm long) occur because they are intercepted and truncated by the conventional 180$^{\deg}$ domain walls. These results reveal the unusual charged domain structures in Ca$_{3-x}$Sr$_x$Ti$_2$O$_7$ and will be useful for understanding their formation process.

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Hiroshi Nakajima, Koji Shigematsu, Yoichi Horibe, Shigeo Mori, Yasukazu Murakami. 2019-07-18. Charged domain walls and crystallographic microstructures in hybrid improper ferroelectric Ca$_{3-x}$Sr$_x$Ti$_2$O$_7$. https://doi.org/10.2320/matertrans.mt-mi2019006

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