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arXiv · 2208.05499

Spin-carrier coupling induced ferromagnetism and giant resistivity peak in EuCd$_2$P$_2$

Veronika Sunko·Yue Sun·Mayia Vranas·Christopher C. Homes·Changmin Lee·Elizabeth Donoway·Zhi-Cheng Wang·Sudhaman Balguri·Mira B. Mahendru·Alejandro Ruiz·Brandon Gunn·Rourav Basak·Enrico Schierle·Eugene Weschke·Fazel Tafti·Alex Frano·Joseph Orenstein
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Abstract

EuCd$_2$P$_2$ is notable for its unconventional transport: upon cooling the metallic resistivity changes slope and begins to increase, ultimately 100-fold, before returning to its metallic value. Surprisingly, this giant peak occurs at 18K, well above the N\'{e}el temperature ($T_N$) of 11.5K. Using a suite of sensitive probes of magnetism, including resonant x-ray scattering and magneto-optical polarimetry, we have discovered that ferromagnetic order onsets above $T_N$ in the temperature range of the resistivity peak. The observation of inverted hysteresis in this regime shows that ferromagnetism is promoted by coupling of localized spins and itinerant carriers. The resulting carrier localization is confirmed by optical conductivity measurements.

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Veronika Sunko, Yue Sun, Mayia Vranas, Christopher C. Homes, Changmin Lee, Elizabeth Donoway, Zhi-Cheng Wang, Sudhaman Balguri, Mira B. Mahendru, Alejandro Ruiz, Brandon Gunn, Rourav Basak, Enrico Schierle, Eugene Weschke, Fazel Tafti, Alex Frano, Joseph Orenstein. 2022-08-10. Spin-carrier coupling induced ferromagnetism and giant resistivity peak in EuCd$_2$P$_2$. https://doi.org/10.1103/physrevb.107.144404

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