Experimental determination of flexoelectric coefficients in <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:msub><mml:mi>SrTiO</mml:mi><mml:mn>3</mml:mn></mml:msub><mml:mo>,</mml:mo><mml:mo> </mml:mo><mml:msub><mml:mi>KTaO</mml:mi><mml:mn>3</mml:mn></mml:msub><mml:mo>,</mml:mo><mml:mo> </mml:mo><mml:msub><mml:mi>TiO</mml:mi><mml:mn>2</mml:mn></mml:msub></mml:math>, and <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:msub><mml:mi>YAlO</mml:mi><mml:mn>3</mml:mn></mml:msub></mml:math> single crystals
Christopher A. Mizzi, Binghao Guo, Laurence D. Marks
Abstract
We report experimental values for the flexoelectric responses of ${\mathrm{SrTiO}}_{3}, {\mathrm{KTaO}}_{3}, {\mathrm{TiO}}_{2}$, and ${\mathrm{YAlO}}_{3}$ single crystals using a three-point bending approach. We find all samples possess a linear flexoelectric response with effective short-circuit flexoelectric coefficients $\ensuremath{\sim}|1--10|\phantom{\rule{0.16em}{0ex}}\mathrm{nC}/\mathrm{m}$. Flexocoupling voltages computed from these measured effective flexoelectric coefficients are found to significantly vary across the investigated materials and refute the previous suggestions that they should be $\ensuremath{\sim}|1--10|$ V. Importantly, we find that low dielectric constant materials can have large flexocoupling voltages exceeding nominal expectations.