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arXiv · 1409.2960

Visualization of ferroelectric domains in boracite using emission of terahertz radiation

Y. Kinoshita·N. Kida·M. Sotome·R. Takeda·N. Abe·M. Saito·T. Arima·H. Okamoto
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Abstract

We report on the emission of terahertz radiation by irradiation of femtosecond laser pulses in non-centrosymmetric paraelectric and ferroelectric phases of Co$_3$B$_7$O$_{13}$I boracite. The Generation of the terahertz waves in both phases is caused by optical rectification via a second-order nonlinear optical effect. In the ferroelectric phase, we successfully visualized ferroelectric domains by analyzing the polarization state of the terahertz wave radiated from the crystal. In a large area of the crystal ($\sim$ 500 $\times$ 500 $μ$m$^2$), the observed polarization vector of the radiated terahertz wave was tilted from directions of spontaneous polarization, i.e., [100]$_{\rm cub}$, [010]$_{\rm cub}$, and [001]$_{\rm cub}$ in cubic setting, which can be explained by the presence of a ferroelectric 90$^\circ$ domain wall of the (101)$_{\rm cub}$ plane.

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Y. Kinoshita, N. Kida, M. Sotome, R. Takeda, N. Abe, M. Saito, T. Arima, H. Okamoto. 2014-09-10. Visualization of ferroelectric domains in boracite using emission of terahertz radiation. https://doi.org/10.7567/jjap.53.09pd08

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