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arXiv · 2302.01627

Simultaneous measurement of specific heat and thermal conductivity in pulsed magnetic fields

Abstract

We report an experimental setup for simultaneously measuring specific heat and thermal conductivity in feedback-controlled pulsed magnetic fields of 50 msec duration at cryogenic temperatures. A stabilized magnetic field pulse obtained by the feedback control, which dramatically improves the thermal stability of the setup and sample, is used in combination with the flash method to obtain absolute values of thermal properties up to 37.2 T in the 2 K to 16 K temperature range. We describe the experimental setup and demonstrate the performance of the present method with measurements on single crystal samples of the geometrically frustrated quantum spin-dimer system SrCu$_2$(BO$_3$)$_2$. Our proof-of-principle results show excellent agreement with data taken using a standard steady-state method, confirming the validity and convenience of the present approach.

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Tetsuya Nomoto, Chengchao Zhong, Hiroshi Kageyama, Yoko Suzuki, Marcelo Jaime, Yoshiaki Hashimoto, Shingo Katsumoto, Naofumi Matsuyama, Chao Dong, Akira Matsuo, Koichi Kindo, Koichi Izawa, Yoshimitsu Kohama. 2023-02-03. Simultaneous measurement of specific heat and thermal conductivity in pulsed magnetic fields. https://doi.org/10.1063/5.0143875

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