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

TL;DR

This paper introduces an experimental setup capable of simultaneously measuring specific heat and thermal conductivity in pulsed magnetic fields up to 37.2 T at cryogenic temperatures, enabling accurate thermal property characterization.

Contribution

The paper presents a novel method combining feedback-controlled pulsed magnetic fields with the flash technique for simultaneous thermal measurements at high fields and low temperatures.

Findings

Excellent agreement with steady-state measurements validates the method.

The setup achieves stable measurements in 50 ms pulsed fields.

Demonstrated on SrCu₂(BO₃)₂ single crystals.

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.