Successive magnetic transitions and multiferroicity in layered honeycomb BiCrTeO$_{6}$

Arkadeb Pal; P. H. Lee; J. Khatua; C. W. Wang; J. Gainza; A. Fitch; Thomas J. Hicken; H. Luetkens; Y. J. Hu; Ajay Tiwari; D. Chandrasekhar Kakarla; J. Y. Lin; K. Y. Choi; G. R. Blake; H. D. Yang

arXiv · 2512.13387

Successive magnetic transitions and multiferroicity in layered honeycomb BiCrTeO$_{6}$

Arkadeb Pal·P. H. Lee·J. Khatua·C. W. Wang·J. Gainza·A. Fitch·Thomas J. Hicken·H. Luetkens·Y. J. Hu·Ajay Tiwari·D. Chandrasekhar Kakarla·J. Y. Lin·K. Y. Choi·G. R. Blake·H. D. Yang

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Abstract

Low-dimensional magnetic systems based on honeycomb lattices provide a promising platform for exploring exotic quantum phenomena that emerge from the intricate interplay of competing spin, orbital, lattice, and dipolar degrees of freedom. Here, we present a comprehensive study of the layered honeycomb lattice antiferromagnet BiCrTeO$_6$ using magnetization, specific heat, muon spin--relaxation ($\mu$SR) spectroscopy, dielectric, pyrocurrent, and high-resolution synchrotron X-ray diffraction (SXRD) measurements. Our results reveal an array of intriguing and strongly correlated phenomena, including two successive antiferromagnetic transitions at $T_{\rm N1}\approx16$ K and $T_{\rm N2}\approx11$ K, a pronounced magnetodielectric coupling effect, and ferroelectric order at $T_{\rm N2}$. Consequently, this compound emerges as a new spin-driven multiferroic system. The SXRD analysis reveals a magnetoelastic-coupling-induced structural phase transition at $T_{\rm N2}$, characterized by a symmetry lowering from P$\bar{3}$1c (163) to P31c (159), which likely triggers the onset of ferroelectricity. In addition to its low-temperature multiferroic behavior, the system exhibits dielectric relaxor characteristics at higher temperatures within the paramagnetic region ($T<50$ K), which is intrinsically linked to the antisite disorder of Cr and Te atoms.

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Arkadeb Pal, P. H. Lee, J. Khatua, C. W. Wang, J. Gainza, A. Fitch, Thomas J. Hicken, H. Luetkens, Y. J. Hu, Ajay Tiwari, D. Chandrasekhar Kakarla, J. Y. Lin, K. Y. Choi, G. R. Blake, H. D. Yang. 2025-12-15. Successive magnetic transitions and multiferroicity in layered honeycomb BiCrTeO$_{6}$. https://arxiv.org/abs/2512.13387

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