Low-temperature magnetic crossover in the topological kagome magnet TbMn6Sn6

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$${T}_{{{{{{{{\rm{C1}}}}}}}}}^{* }$$ ≃ 120 K and finally freeze into static patches with ideal out-of-plane order belowT$_{C1}$ ≃ 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 staticc-axis ferrimagnetic patches and the topological electronic properties in TbMn$_{6}$Sn$_{6}$

An expectation maximization framework for an improved tissue characterization using ultrasounds

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Double differential neutron spectra generated by the interaction of a 12 MeV/nucleon 36^{36}S beam on a thick nat^{nat}Cu target

International audienceDouble differential neutron spectra (energy, angle) originating from a thick nat Cu target bombarded by a 12 MeV/nucleon 36 S 16+ beam were measured by the activation method and the Time-of-flight technique at the Grand Accélérateur National d’Ions Lourds (GANIL). A neutron spectrum unfolding algorithm combining the SAND-II iterative method and Monte-Carlo techniques was developed for the analysis of the activation results that cover a wide range of neutron energies. It was implemented into a graphical user interface program, called GanUnfold. The experimental neutron spectra are compared to Monte-Carlo simulations performed using the PHITS and FLUKA codes

Experimental approach to measure thick target neutron yields induced by heavy ions for shielding

Double differential (angular and energy) neutron distributions were measured using an activation foil technique. Reactions were induced by impinging two low-energy heavy-ion beams accelerated with the GANIL CSS1 cyclotron: (36S (12 MeV/u) and 208Pb (6.25 MeV/u)) onto thick natCu targets. Results have been compared to Monte-Carlo calculations from two codes (PHITS and FLUKA) for the purpose of benchmarking radiation protection and shielding requirements. This comparison suggests a disagreement between calculations and experiment, particularly for high-energy neutrons

Experimental approach to measure thick target neutron yields induced by heavy ions for shielding

Double differential (angular and energy) neutron distributions were measured using an activation foil technique. Reactions were induced by impinging two low-energy heavy-ion beams accelerated with the GANIL CSS1 cyclotron: (36S (12 MeV/u) and 208Pb (6.25 MeV/u)) onto thick natCu targets. Results have been compared to Monte-Carlo calculations from two codes (PHITS and FLUKA) for the purpose of benchmarking radiation protection and shielding requirements. This comparison suggests a disagreement between calculations and experiment, particularly for high-energy neutrons