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High-frequency dielectric anomalies in a highly frustrated square kagomé lattice nabokoite family compounds ACu7(TeO4)(SO4)5Cl (A=Na,K,Cs,Rb)
Journal of Magnetism and Magnetic Materials. 2024. Vol. 592. Article 171786.
Ya.V.Rebrov, V.N.Glazkov, Murtazoev A. F., Dolgikh V. A., Berdonosov P. S.
Nabokoite family compounds ACu7(TeO4)(SO4)5Cl (A = Na, K, Cs, Rb) are candidates for the experimental realization of highly-frustrated 2D square kagomé lattice (SKL). Their magnetic subsystem includes SKL layers decorated by additional copper ions. All members of this family are characterized by quite high Curie–Weiss temperatures ( 80–200 K), but magnetic ordering was reported only for Na and K compounds at a much lower temperatures below 4 K. We report here results of the study of high-frequency ( ~10 GHz) dielectric properties of this family of compounds. Our study revealed presence of the strong dielectric anomaly both in the real and imaginary parts of high-frequency dielectric permittivity for Na and K compounds approx. 100 and 26 K, correspondingly, presumably related to antiferroelectric ordering. Additionally, much weaker anomalies were observed at approx. 5 K indicating possible interplay of magnetic and lattice degrees of freedom. We discuss possible relation between the structure rearrangements accompanying dielectric anomalies and a delayed magnetic ordering in the nabokoite family compounds.
Keywords: frustrated magnets
Publication based on the results of:
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абота редакции научного журнала «Труды Московского физико-технического института» (кратко «Труды МФТИ»), редакционной коллегии и редакционного совета осуществляется в соответствии с Положением, утвержденным ректором института. В состав редакционной коллегии входят руководители института, факультетов, институтских и факультетских кафедр. Главный редактор журнала —президент МФТИ, член-корр. РАН Кудрявцев Н.Н.
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Filippova A. V., Yurchenko N. Y., Smirnov S. A. et al., Journal of Alloys and Compounds 2026 No. 1074 Article 189162
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Ребров Я. В., Glazkov V., Murtazoev A. F. et al., / Series cond-mat "arxiv.org". 2023.
Nabokoite family compounds ACu7(TeO4)(SO4)5Cl (A=Na, K, Cs, Rb) are one of the candidates for the evasive spin-liquid state predicted for highly-frustrated square kagome lattice (SKL). Their magnetic subsystem includes SKL layers decorated by additional copper ions. All members of this family are characterized by quite high Curie-Weiss temperatures (∼80−200 K), but magnetic ordering was reported ...
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