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arXiv · 1805.07940

Field-rotational magnetocaloric effect: A new experimental technique for accurate measurement of the anisotropic magnetic entropy

Shunichiro Kittaka·Shota Nakamura·Hiroaki Kadowaki·Hiroshi Takatsu·Toshiro Sakakibara
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Abstract

We developed a new technique for measuring the thermodynamic entropy as a function of the magnetic field angle. This technique enables high-resolution angle-resolved measurements of the entropy in an unprecedentedly short measuring time. When the magnetic field is rotated under adiabatic conditions, the sample temperature changes owing to the field-angle variation of its entropy, which is referred to as the rotational magnetocaloric effect. By investigating this effect along with the specific heat, the field-angle dependence of the entropy can be determined. To demonstrate this technique, we chose the spin-ice compound Dy$_2$Ti$_2$O$_7$ as a benchmark and showed good agreement between the measured and theoretical entropies as a function of the field angle. This development provides a new approach to studying condensed-matter physics, in which multiple degrees of freedom play an important role.

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Shunichiro Kittaka, Shota Nakamura, Hiroaki Kadowaki, Hiroshi Takatsu, Toshiro Sakakibara. 2018-05-21. Field-rotational magnetocaloric effect: A new experimental technique for accurate measurement of the anisotropic magnetic entropy. https://doi.org/10.7566/jpsj.87.073601

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