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Elastic anomalies associated with domain switching in BaTiO$_3$ single crystals under in-situ electrical cycling

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 نشر من قبل Guillaume Nataf
 تاريخ النشر 2019
  مجال البحث فيزياء
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 تأليف D. Pesquera




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The elastic response of BaTiO$_3$ single crystals during electric field cycling at room temperature has been studied using in-situ Resonant Ultrasound Spectroscopy (RUS), which allows monitoring of both the elastic and anelastic changes caused by ferroelectric polarization switching. We find that the first ferroelectric switching of a virgin single crystal is dominated by ferroelastic 90{deg} switching. In subsequent ferroelectric switching, ferroelastic switching is reduced by domain pinning and by the predominance of 180{deg} ferroelectric domains, as confirmed by polarized light microscopy. RUS under in-situ electric field therefore demonstrates to be an effective technique for the investigation of electromechanical coupling in ferroelectrics.



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