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arXiv · 1409.4846

Birefringence of silica hydrogels prepared under high magnetic fields reinvestigated

Atsushi Mori·Takamasa Kaito·Hidemitsu Furukawa·Masafumi Yamato·Kohki Takahashi
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Abstract

Birefringence is an indicator of structural anisotropy of materials. We measured the birefringence of Pb(II)-doped silica hydrogels prepared under a high magnetic field of various strengths. Because the silica is diamagnetic, one does not expect the structural anisotropy induced by a magnetic field. In previous work [Mori A, Kaito T, Furukawa H 2008 Mater. Lett. 62 3459-3461], we prepared samples in cylindrical cells made of borosilicate glass and obtained a preliminary result indicating a negative birefringence for samples prepared at 5T with the direction of the magnetic field being the optic axis. We have measured the birefringence of Pn(II)-doped silica hydrogels prepared in square cross-sectional cells made of quartz and reverted the previous conclusion. Interestingly, the magnetic-influenced silica hydrogels measured have been classified into four classes: two positive birefringent ones, no birefringent one, and negative birefringent one. Proportionality between birefringence and the strength of magnetic field is seen for the former two.

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Atsushi Mori, Takamasa Kaito, Hidemitsu Furukawa, Masafumi Yamato, Kohki Takahashi. 2014-09-17. Birefringence of silica hydrogels prepared under high magnetic fields reinvestigated. https://doi.org/10.1088/2053-1591%2F1%2F4%2F045202

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