Low-temperature magnetic crossover in the topological kagome magnet TbMn6Sn6
C. Mielke, Wenlong Ma, Vladimir Pomjakushin, O. Zaharko, Simone Sturniolo, X. Liu, Victor Ukleev, J. S. White, Jia‐Xin Yin, Stepan S. Tsirkin, Camilla Buhl Larsen, Tyler A. Cochran, M. Medarde, Victor Porée, Debarchan Das, Ritu Gupta, Chennan Wang, J. Chang, Ziqiang Wang, R. Khasanov, Titus Neupert, A. Amato, Leandro Liborio, Shuang Jia, M. Zahid Hasan, H. Luetkens, Zurab Guguchia
Abstract
Abstract Magnetic topological phases of quantum matter are an emerging frontier in physics and materials science, of which kagome magnets appear as a highly promising platform. Here, we explore magnetic correlations in the recently identified topological kagome system TbMn 6 Sn 6 using muon spin rotation, combined with local field analysis and neutron diffraction. Our studies identify an out-of-plane ferrimagnetic structure with slow magnetic fluctuations which exhibit a critical slowing down below $${T}_{{{{{{{{\rm{C1}}}}}}}}}^{* }$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:msubsup><mml:mrow><mml:mi>T</mml:mi></mml:mrow><mml:mrow><mml:mi>C1</mml:mi></mml:mrow><mml:mrow><mml:mo>*</mml:mo></mml:mrow></mml:msubsup></mml:math> ≃ 120 K and finally freeze into static patches with ideal out-of-plane order below T C1 ≃ 20 K. We further show that hydrostatic pressure of 2.1 GPa stabilises the static out-of-plane topological ferrimagnetic ground state in the whole volume of the sample. Therefore the exciting perspective arises of a magnetically-induced topological system whose magnetism can be controlled through external parameters. The present results will stimulate theoretical investigations to obtain a microscopic understanding of the relation between the low-temperature volume-wise magnetic evolution of the static c -axis ferrimagnetic patches and the topological electronic properties in TbMn 6 Sn 6 .