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arXiv · 1807.07192

Measurement of the angle dependence of magnetostriction in pulsed magnetic fields using a piezoelectric strain gauge

Abstract

We present a high resolution method for measuring magnetostriction in millisecond pulsed magnetic fields at cryogenic temperatures with a sensitivity of $1.11\times10^{-11}/\sqrt{\rm Hz}$. The sample is bonded to a thin piezoelectric plate, such that when the sample's length changes, it strains the piezoelectric and induces a voltage change. This method is more sensitive than a fiber-Bragg grating method. It measures two axes simultaneously instead of one. The gauge is small and versatile, functioning in DC and millisecond pulsed magnetic fields. We demonstrate its use by measuring the magnetostriction of Ca$_3$Co$_{1.03}$Mn$_{0.97}$O$_6$ single crystals in pulsed magnetic fields. By comparing our data to new and previously published results from a fiber-Bragg grating magnetostriction setup, we confirm that this method detects magnetostriction effects. We also demonstrate the small size and versatility of this technique by measuring angle dependence with respect to the applied magnetic field in a rotator probe in 65 T millisecond pulsed magnetic fields.

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Xiaxin Ding, Yi-Sheng Chai, Fedor Balakirev, Marcelo Jaime, Hee Taek Yi, Sang-Wook Cheong, Young Sun, Vivien Zapf. 2018-07-19. Measurement of the angle dependence of magnetostriction in pulsed magnetic fields using a piezoelectric strain gauge. https://doi.org/10.1063/1.5038741

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