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arXiv · 2205.05555

Zero-field current-induced Hall effect in ferrotoroidic metal

K. Ota·M. Shimozawa·T. Muroya·T. Miyamoto·S. Hosoi·A. Nakamura·Y. Homma·F. Honda·D. Aoki·K. Izawa
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Abstract

We have performed precise Hall measurements for the ferrotoroidic candidate material UNi4B. Below Neel temperature TN ~ 20 K (corresponding to the ferrotoroidic transition temperature), a Hall voltage becomes finite even at zero field and changes proportional to the square of current density; by contrast, it is almost zero above TN. Moreover, we have found that a current-induced magnetization estimated from our Hall effect measurements is qualitatively consistent with the previous directly measured value. These results provide strong evidence for a magnetoelectric phenomenon uniquely in ferrotoroidic metals -- a zero-field nonlinear Hall effect resulting from the current-induced magnetization connecting the ferrotoroidal moments.

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K. Ota, M. Shimozawa, T. Muroya, T. Miyamoto, S. Hosoi, A. Nakamura, Y. Homma, F. Honda, D. Aoki, K. Izawa. 2022-05-11. Zero-field current-induced Hall effect in ferrotoroidic metal. https://arxiv.org/abs/2205.05555

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