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Direct Imaging of Submicron Scale Defect-induced Birefringence in SrTiO$_{3}$ Bicrystals

E. B. McDaniel·J. W. P. Hsu
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Abstract

Using a near-field scanning optical microscope capable of quantitative polarimetry, we map the anisotropic strain fields associated with individual submicron defects near the fusion boundaries of SrTiO$_{3}$ bicrystals. Many defects exhibit unexpected spiral-shape strain patterns, whose handedness is believed to be linked to the bicrystal synthesis process. Direct observation of these defect-induced strain fields helps explain previously observed non-uniformity in the characteristics of high temperature superconductor grain boundary junctions fabricated on SrTiO$_{3}$ bicrystals.

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E. B. McDaniel, J. W. P. Hsu. 1998-02-04. Direct Imaging of Submicron Scale Defect-induced Birefringence in SrTiO$_{3}$ Bicrystals. https://doi.org/10.1063/1.368015

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