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arXiv · 2203.09754

Magnetic field-Temperature Phase Diagram of CeCoSi Constructed by Specific Heat, Magnetoresistivity, and Magnetization Measurements for a Single Crystal

Hiroyuki Hidaka·Shun Yanagiya·Eikai Hayasaka·Yuma Kaneko·Tatsuya Yanagisawa·Hiroshi Tanida·Hiroshi Amitsuka
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Abstract

A Ce-based metallic compound CeCoSi with a tetragonal structure exhibits successive phase transitions: the one whose order parameter is unidentified at T_0 = 12 K and the antiferromagnetic one at T_N = 9.4 K. We performed specific heat, magnetoresistivity (MR), and magnetization measurements for a single crystal CeCoSi at low temperatures in magnetic fields B of up to 14 T and constructed detailed magnetic field--temperature phase diagrams for both B || [100] and [001]. The longitudinal MR measured for B || [100] shows a sign change from negative to positive across T_0 = 13 K updated in the present sample, indicating a clear change in an electronic state. In addition, the constructed magnetic phase diagrams for both the field directions have a B-induced region in each ordered state. The presence of the newly found regions would be attributed to a change in the symmetry of the order parameter or domain alignment by applying B.

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Hiroyuki Hidaka, Shun Yanagiya, Eikai Hayasaka, Yuma Kaneko, Tatsuya Yanagisawa, Hiroshi Tanida, Hiroshi Amitsuka. 2022-03-18. Magnetic field-Temperature Phase Diagram of CeCoSi Constructed by Specific Heat, Magnetoresistivity, and Magnetization Measurements for a Single Crystal. https://doi.org/10.7566/jpsj.91.094701

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